Heres an interesting little puzzle from everyday life.

1. Two friends Jack and Peter are riding (on two different motorbikes) to meet their friend Steve for beer.

 

2. Jack knows the way to Steve's house, but Peter does not. So Jack leads the way and Peter follows at a distance.

 

3. But the traffic is heavy and unpredicatble , and there are situations where the two lose sight of each other. (If you think thats  impossible, you havent seen Bangalore traffic). In such situations, Peter could also (unintentionally ) overtake Jack and be in front.

4. Sadly, they duo do not possess cell phones.

 

Given the situation above, whats the best synchronization method that the two friends can use to reach Steve's house in time for beer ?

 

The puzzle is not as simple as it sounds.

One (sub optimal) solution would be:

"At every intersection, both J and P stop, and wait for the other to catch up."

(But this could also lead to situations where the two are waiting infinitely at successive intersections, after briefly having lost sight of each other. We would have to combine it with a timeout, maybe ?Think about it .)

 

( For fellow-geeks only : How would one relate process synchronization primitives to this problem? )

This problem manifests itself in several other forms.....for example, when two tourists want to meet at a tourist place that neither of them has been to before, how do they set up their rendezvous? I'll state the complete problem, with its limitations, in future blogs. )

 For now, lets have some comments on how Peter and Jack can get to some beer.

Got my hands on the new Asterix comic book , 'Asterix and the Falling Sky'.

(In French : Le Ciel lui Tombe sur la Tete)

And dont worry, I  wont give the plot away in this blog.

I bought  the French version of the book.  No I  do not understand the language, but the urge was just too great to resist !

 

I have all the Asterix books back home, and sincerely devour one at least every  week. And fill myself with Asterix trivia too. Yes, Im a *big* fan of the books.

(Question for you : whats the name of the postman at the Gaulish village ? In the English version. )

Boy , was I disappointed. The plot is thin, there is no adventure, the characters are flat and the humour is slapstick ! (Well, I would not have understood  the French puns anyway, but the humor in this book is targetted at three year olds... you can just tell. ) 

In the new  Harry Potter book, an 'important' character was killed. I think its the same in this new Asterix book as well.... they have killed Goscinny.

The man who originally scripted the Asterix stories  is dead, but they seem to have pulled him out of his grave and slaughtered him yet again with this book.

 

Dont get me wrong. I do not hate Uderzo for all the books that he created after Goscinny's death.

 I admire and respect Uderzo, and still believe that he deserves to , and is capable of  carrying on the Asterix legacy.

But mon dieu , this one was awful, Mr Uderzo !

   

 

 

Two weeks without a laptop and Im getting withdrawal symptoms already.

( Are those bite marks on my arms ? Where do my pillows mysteriously disappear every night ?)

Acer took a week and a half to return my laptop to me from repair ( but decided to conveniently keep my battery, CDs  and powercords).

Several phone calls later,  they sent it to me . When I put it all together, it didnt work. The hard disk was blown.

 

The laptop is back with Acer now.

I have  a weeks break in Europe coming up , and have not planned my trip at all, since there was no laptop and I was running around to get things sorted out .

 

 

So by now ,  you must have heard of  the OpenSolaris Live CD distro, Belenix .

 

My team mate Moinak worked almost single handedly on this project..there were many late evenings when I would see him walk by my desk looking quite absent-minded, rolling over a build issue in his head.

 

The man finally managed to sort it all out, and he deserves every single bit of appreciation that he gets.

 

I like the name Belenix .......Ive always been a fan of the Asterix[1] comics, and when Moinak walked up one day and suggested the name, I said it reminded me of Belonos from the Asterix books.

 

The  name I suggested though,   for the distro , was 'Utu'.

 

Utu is the Babylonian Sun God. The name is short, sweet , and has great  potential for a logo and a mascot too.

 

(It sounds suspisciously similar to Ubuntu, of which Im a great fan, but hey its just a coincidence.)  

 

But we did not want to run into any trademark issues with UTU (The United Transportation Union), so Moinak chose the name Belenix.

 

I love it already !  I used one of the initial trial CDs that Moinak had  burnt  as an emergency  Rescue CD ... used the grub on it to boot to an Ubuntu partition that had been hidden by a badly attempted Windows reinstall. Neat, eh ?

 

[1] Which reminds me.....Im in France now and have to go visit the Asterix museum here. Is it  good ?

 

Planning to visit Brussels next week and see the Tintin museum there....

 

 

Im in France now..... here on a three month semi-vacation. (That means I still get to check Sun email but not respond to to my manager's mails . Ah ..... the felling ! )

 

And yes ,  I promise not to post pictures of me standing next to the Eiffel tower.

 

Day 1 was not good. My Acer Ferrari 3400 laptop blew its motherboard.( Yeah I know..... the Italians  are not doing well at the races either. Im a Kimi Raikkonen fan , though. Go Kimi !)

 

 

Luckily, I had the sense to lug along my international warranty (Acer calls it the 'passport'. How original.  )

 

So I  got a friend here to call up the Acer  service center (they  spoke only French :-)) and report the problem; they promptly sent a TNT guy over to pick up the laptop.

 

I thought that was nice , since the warranty talked about a 'carry-in' warranty only.

 

But thats where the story ends!

 

I was promised an 'email reply' about the status of my laptop, but its been a week now and I havent heard from them. I sent an email  in reply to the original email that was sent out to me, but I got a message (in French) that asked me to call up some phone numbers.

 

We tried all afternoon today, but could not get through to an operator. (And I didnt like the music , either :-))

 

No , Im not complaining (yet), but Im surprised at the customer service. 

 

A reassuring email would keep me happy, Acer.

 

Its been a week now ...... I thought I would have the laptop back.  France is cold......I need the AMD heat !

 

Any Acer support folks out there reading my blog?

 

 IMO, Sun is colored a distinct shade of Ferrari red (all those Acer AMD laptops we have on campus ),  a shade  dark enough for Acer to give  me some extra TLC !

 

 

 

 

 

 

 

 

I was reading Sean Doherty's review

of Sun Ray Server Software 3.1.

Sean seems impressed by the ease of installation and the performance over low bandwidth connections.Thats nice to hear.

But he notes one 'drawback' too:

 

Bad:

 Requires Sun Ray DTUs (Desktop Units)

ie, one needs a Sunray box to connect to a Sunray server.

 

 

 

I couldnt agree more. This issue could be interpreted in two ways. Allow me to explain.

The Value Proposition of the Sunray is different for different target segments.

At a broad level, lets take two target segments - the 'IT Operations department' segment , and the 'End Users' segment , and see how this 'issue' affects them.

 

 

For ITOps, the Sunray brings lower initial costs, lower operating costs, scalability, resource-sharing -- you know the rest.

1. For the ITOps segment, the issue above could be interpreted as:

"If I have to buy more sunray desktops, it means more investment.

( Though sunrays are way cheaper than regular desktops.)"

OR

"Hey cant we just reuse our existing desktop boxes in someway?"

These are mere logistics issues, the subject of another blog..... it can be proven that Sunrays are more cost-effective in the longer run, depending on the needs.

 

 

 

For End Users, the Sun Ray brings mobility.

Not having to close all your windows when you leave your desk , and being able to retrive your work from anyplace, anytime is amazing.

I use it, therefore I can vouch for it.

This single feature alone is enough to push most users onto a SunRay.

2. For the End Users segment , the 'issue' above means

" Cant I access my Sunray session from a non SunRay box? "

And therein lies the problem.

 

 

We should remember that the Sunray will, more often than not, be installed in heterogenous environments containing a mix of Solaris, Windows and Mac boxes.

In such environments, TO ENSURE TOTAL MOBILITY, the SUNRAY SESSION MUST RUN ON NON SUNRAY BOXES,( maybe in a separate window).

Lets call this a 'SunRayLite session'.

A SunRayLite session on a Windows box sounds feasible from a technical perspective, ie getting the X session exported securely, with some client software on the windows box.

The performance may not be the same as that on a regular Sunray DTU, but it brings mobility.

 

I have friends who run VNC sessions on their solaris boxes, and connect to this session from their laptops (windows, solaris , Mac), desktops, from home, from office, etc...

....creating their own equivalent of a mobile Sunray session.

VNC performance is not great over low bandwidths , but note that they are ready to sacrifice performance for mobility.

 

 

Users will adapt-- they'll find out ways of running high bandwidth apps locally if necessary , etc.

Whats important here, is to give the user a choice and make them understand that the SunRayLite session is for mobility, and its much faster on a fullfledged Sunray DTU.

I dont know if this feature already exists.

It probably does, because it looks technically feasible. But it does not seem to be marketed .

IMHO, this feature should be bundled and marketed with the rest of the Sunray offering.

This will ensure a foot-in-the-door for Sun Sales into primarily Windows environments.

 

 

 

Im back -  after  a couple of weeks in blog-hibernation, thanks to a sudden upshoot in workload.

I had an interesting experience at my bank this Thursday.
I met a man who wanted to transfer $1000 to someone in the US. I overheard  him telling the bank employees that he had won a 'lottery'  in Nigeria, and he was sending this money across as  'processing fees'. Of course the folks at the bank  tried explaining to him that this was a scam.  When  I left the bank, I noticed he was still not convinced that he was being tricked; the Nigerian seemed to have done a good job of convincing  him :-)

It was quite shocking to see how gullible people can get, and also how well spread out the scam-network actually is. I remember reading in the Bangalore newspapers (a few months ago) that  the local police had arrested some Nigerian  scamsters who were in Bangalore to collect  money from some unsuspecting  folks.

In other news, Google finally seems to think that I am the Internet's official 'Jaiprasad':

http://www.google.co.in/search?q=jaiprasad

The closest competition is from a Book of baby names, and also from a jaiprasad who works for the Bangalore city corporation. (In fact he owns most of the other google hits....but hey, I own the hit that matters :-) !)

I have always looked for a 'truss -p ' equivalent  for java.
A simple utility, which, when pointed at a running java process,
can look beneath the hood and show you all the method invocations happening underneath.

The Java dtrace agents project   caught my eye today .
Here was a chance to hack together a small utility, and also learn more about dtrace scripting on Solaris 10.
(I must admit, I was putting this off for a while now.)

Now, this is my first attempt at dtrace code- written in a day - so pardon any glaring loopholes.
And the output formatting is not pretty - its merely a proof of concept, for now.
I'll fix these as I make progress - stay tuned.
I would also urge you to take a look at Bryan's and Adam's excellent blogs on this  topic.
For me , these blogs were like the last-minute cram before the exams, if you know what I mean.

What this code does

When pointed   at a  running java process,
a) It prints select method invocations from inside the process , in an indented fashion.
b) Upon exit, it prints a summary of the total time spent (in nanoseconds) in each method invocation.
It currently works only for the tetris jar. A couple of minor tweaks (come back tomorrow :-) ) should make it generic.


This blog takes off from Bryan's  blog about dtracing  Per Cerderberg's Java implementation of Tetris.
1. Instead of tracing out all methods, I only look for methods from  classes immediately  inside the jar file.
A quick  jar -tvf on the jar-file showed that the classes were part of the "net/percederberg/tetris/" hierarchy.
So I look only for methods from classes immediately within the "net/percederberg/tetris"hierarchy.
Henc the hacked-up check :

/stringof(copyin(arg0,7)) == "net/per" / 

The code

#pragma D option quiet

/*jtruss.d */

BEGIN
{

	self->indent=0;
	self->elapsed=0;
}

dvm$target:::method-entry
/stringof(copyin(arg0,7)) == "net/per" / 
{

	self->elapsed=timestamp;
	self->indent += 2;
	printf("%*s -> %s:%s  \n", self->indent, "",
	copyinstr(arg0), copyinstr(arg1));
}

dvm$target:::method-return
/stringof(copyin(arg0,7)) == "net/per" / 
{
	self->elapsed=timestamp-self->elapsed;
	printf("%*s <- %s:%s  %10u \n", self->indent, "",
	copyinstr(arg0), copyinstr(arg1), self->elapsed );
	@time[strjoin(strjoin(basename(copyinstr(arg0)), "."),copyinstr(arg1))]
	= sum(self->elapsed);
	
	self->indent -= 2;
	self->elapsed =0; 

}

END
{
        printa("%-70s %10@u\n", @time);
}

Invoking it

$export LD_LIBRARY_PATH=/path/to/djvm/build/sparc/lib
$ java -Xrundvmti:all -cp $LD_LIBRARY_PATH  -jar ./tetris-1.2-bin.jar &
[1] 530
$dtrace -s  ./jtruss.d -p  530 

Sample output

   -> net/percederberg/tetris/Game$GamePanel:paint  

   <- net/percederberg/tetris/Game$GamePanel:paint     2037872 

   -> net/percederberg/tetris/Game$2:actionPerformed  

     -> net/percederberg/tetris/Game$GamePanel:access$800  

     <- net/percederberg/tetris/Game$GamePanel:access$800       45955 

     -> net/percederberg/tetris/Game:access$1000  

       -> net/percederberg/tetris/Game:handleButtonPressed  

         -> net/percederberg/tetris/Game:handleStart  

           -> net/percederberg/tetris/Game:randomFigure  

           <- net/percederberg/tetris/Game:randomFigure     1649509 

           -> net/percederberg/tetris/Figure:rotateRandom  

             -> net/percederberg/tetris/Figure:setRotation  

               -> net/percederberg/tetris/Figure:isAttached  

               <- net/percederberg/tetris/Figure:isAttached       38746 

             <- net/percederberg/tetris/Figure:setRotation  1931045631 

           <- net/percederberg/tetris/Figure:rotateRandom  1931120240 

         <- net/percederberg/tetris/Figure:getRotation  1931222241 

       <- net/percederberg/tetris/SquareBoard:access$000  1933261195 

     <- net/percederberg/tetris/SquareBoard:access$100  1933371667 

<snip>

.

.

<snip - partial output after control-c >

Figure.setRotation                                                     3960284127717311

SquareBoard$SquareBoardComponent.paintComponent                        7920568746094973

Figure.getRelativeX                                                    7920569312267083

Figure.isInside                                                        10560759082912481

SquareBoard.isSquareEmpty                                              10560759083723630

To be done: ("Come-back-tomorrow")

• It currently works only for the tetris jar.
• A couple of minor changes (in the method-entry and method-exit checks ) should make it generic.
• More  enhancements .....

I must admit that  once you have it all figured out, dtrace hits you hard. Im hooked.

Technorati Tag: OpenSolaris
Technorati Tag: Solaris
Technorati Tag: DTrace

Heres a (slashdotted) article that talks about the Death of the 'Folder' Metaphor on desktops:

http://www.wired.com/news/mac/0,2125,67774,00.html?tw=wn_story_top5

<excerpt>
"Another indication of how we may work in the future is provided by Tiger's Smart Folders feature,
which lets the user save the results of a Spotlight search as a virtual folder that automatically updates
as new items matching the search are added to the system."
</excerpt>

The article essentially talks  about how,
 with increasing amounts of data and information in todays world,
traditional methods of organizing information on the desktop are beginning to show their age.

This reminded me of another article that I had read a while ago,   about the  LifeStreams Project:

http://www.cs.yale.edu/homes/freeman/lifestreams.html

Here is the definition of a LifeStream:
"A lifestream is a time-ordered stream of documents that functions as a diary of your electronic life;
every document you create and every document other people send you is stored in your lifestream.
The tail of your stream contains documents from the past (starting with your electronic birth certificate).
Moving away from the tail and toward the present, your stream contains more recent documents ---
papers in progress or new electronic mail;
other documents (pictures, correspondence, bills, movies, voice mail, software) are stored in between."

In the Lifestreams Project, the authors talk about the concept of 'SubStreams',
where information is organized based on the results of a search string,
and the contents are dynamically updated as new data/information matches the search criteria.

This is essentially what the  wired.com article talks about.

A few years ago, if a reader had chanced upon the LifeStreams project, he would have dismissed it as 'academic research  stuff',
but the rapid evolution of  information  is making it a reality today.
The LifeStreams project, as you realize, is not just about information stored in folders on disk;
its about  your information stored  'eveywhere'.


Its another one of those 'Research meets Reality' moments...when it hits you, it hits you hard.

Im often asked to help out with OS installations by friends at Sun /outside, on their machines.

The most common scenario is that its a Windows machine, and the user wants to  multiboot windows/linux on it.
(I  offer to throw in  a Solaris installation for free  :-) )
 
This is the usual cycle:

1. Preview : Does solaris / linux have all the drivers for the hardware on this box ?
2. Backup : Backup data
3. Partition :Repartition the disk to accommodate the new OS.
   
4. Install: Install

Step 1 is kinda easy; popping in a Linux Live CD  does the trick. ( I carry  a Ubuntu Hoary preview CD for this.)

Step 2  is also easy, if theres a CD writer around. If a CD writer is not available, and the machine is networked, you can also use
PartImage  for backing up entire partitions, if required.

Step 3 -  Repartitioning - is easy, using the disk tools that come with every linux installer CD.
However,  The System Rescue CD is a very useful CD to carry around during installations.
It offers a wonderful GUI (Qtparted - a PartitionMagic clone) thats very easy to use.
 It also offers partimage on the same CD. Add to this a host of other useful utilities; this makes the CD a must-have.

So why am I blogging about this ? For two reasons:
1. If you frequently install OSes , keep  a copy of the System Rescue CD at hand -its very useful.
2. Can Step 1 (check if Linux works on this machine) be achieved without a  Live CD?

Is there a Windows program which can:

• list out all hardware on the machine
• connect to an online database and check if  <the-chosen-linux-distro>  supports the complete list?

IMO, this would go a long way in increasing the number of Linux evaluations/installs.  
 

Im at home, watching  Mary Pierce on court (she's trailing 1-5 in set 1 of the french open finals) ,  and typing away on my AMD-Ferrari-3400.

The Ferrari  is  triple-boot -
It came with  Windows ( XP - I think.  I  rarely  boot into it , but I have let it have its own tiny partition - the disk is 80 gig anyway. )
On the other partitions, I have Solaris 10 (souped up with ferrari-stuff that the internal community here regularly churns out )
and Ubuntu Linux, which, according to Distrowatch, is the most popular linux distro today.

When I sit back and think about it , I realize that  my friends here run various flavors  of linux on their Ferraris - mandrake, suse, gentoo,redhat, core-debian, etc.
( Of course,all  this is alongside Solaris 10 . Theres a  passion that my team has for solaris 10 - maybe the fact that  we contribute to the solaris code base everyday has something to do with it  :-)  )

So why did they choose  the different linux distros ?

I choose Ubuntu simply because I liked the branding and  the look-and-feel.
( Of course I would love to sit down  one weekend and try a Gentoo compile; but weekends are shrinking these days).

The bleeding-edge-linux-users went for Gentoo, (thanks to this guy, who singlehandedly  moved them over from Fedora).
The risk-averse folks went for Suse and Fedora.
The suse DVD seemed to be packed with features - that attracted many folks too.
There were (not surprisingly) very few mandrake installs - their 'linux for housewives' branding  (pardon the stereotype reference ) did not go well with a team full of engineers bred on Solaris.
Its an ego thing, I guess.


Footnote:
The distrowatch blurb on Solaris says:
" Although based on a number of open standards, Solaris is proprietary rather than free software in terms of licensing."
Times are changing  --  watch this space:
http:// www.opensolaris.org

Meanwhile, the new Knoppix release   is out....

-OR-

How should the folks at WinLibre brand their  product?

Winlibre is a bundle of Open Source Desktop s/w (browser, office suite, chat client, mp3 player etc) for Windows.
I have always felt that to switch everyday-desktop-users  to Open Source, one should follow a 'Top down' approach. WinLibre fits nicely into this philosophy.
But WinLibre is relatively unknown, what should they do to strengthen their brand?
Here are some thoughts.

1) Get a 'philosophy'.

In communities , thats one way of attracting eyeballs ; thats what differentiates your project from , say, 'Yet-another-functionally-rich-project-on-sourceforge'.
 A 'product' provides functionality, a 'brand' provides an experience.
A philosophy is one step towards that experience.

So what should the WinLibre philosophy be?
a) Of course, it should draw its roots from the Open Source philosophy.
b) Atop it, the WinLibre philosophy should probably  talk about how it plans to spread the use of open source products  by embracing Windows too, giving the user more choice.

The 'Positioning' statement  of the WinLibre brand should be
"Free Software on Windows for Everyday Users".

Brand imagery

Change the name 'Winlibre' to something thats more easy to pronounce, and is more global. (WinLibre sounds distinctly European).

Build brand-imagery on the front page of the website (more 'happy/free' photograph-images, distinct fonts,logo -- see what the Ubuntu  folks have done.)

The current front page is too 'geeky';  its not for everyday users.It should be moved to a 'WinLibre Project' page inside the site.
The new front page should feature only  the brand imagery , and the Winlibre philosophy.


Know the brand's target audience

Lets think of the target market for Winlibre. This bundle is not targeted at the developer/techie community. Instead, its more towards everyday PC users (Grandma!) For these users,

a)'Open Source' means nothing; 'Free to modify' means nothing.

For the few of these  who are aware of the Open source movement, they probably respect/admire it greatly , but its not something that would  influence their decision to adopt the software. Having said that, such users would probably want to 'belong to the community'  by using the software, because they admire the community.

Use brand imagery to create a  campaign along the lines of  'I am open - I use Winlibre'.
 Just put these images up for download.  Users  should be able to download/print these - on posters, Tshirts, etc. Or as wallpapers.

b) For everyday users, the fact that its 'free' (from a monetary perspective) is more appealing.

Also the fact thats its perfectly legal.If it can be functionally better (Firefox) then thats just perfect.
The WinLibre suite also offers a rich variety of software.


Therefore, stress on 'Free', 'Legal', 'Feature Rich' and  'Open Source Software', in that order.

Also, resist the temptation to bundle *all* open source windows s/w into the WinLibre bundle in the future .
Only  put in s/w that an average user would use-- NOT cvs clients, etc.
Maybe, give that as a separate 'developer addon' that has to be downloaded separately  but do not add it to the core package; it would merely add to brand dilution and confusion.


More Distribution channels

1. Approach computer  magazines and ask for WinLibre to be included in the magazine CD/DVD.
   This is *big* in countries like India.

2. Use Brand ambassadors (see below)

Brand Ambassadors

Every single techie who knows about Open Source can be a brand ambassador - a virtual WinLibre salesman .
For those of us techies who have tried to switch users from windows to Linux using a Knoppix CD and failed, provide a WinLibre CD as an alternative.

(At the time of writing this blog, there was no Winlibre iso image available for download.
Of course , there is an exe download which can be burned onto a CD.
But a CD-image (with the binaries, an intro to the Winlibre philosophy , a splashimage upon CD-Autorun, etc )is much better -- it contributes to the 'experience'.  Create it!

Also create a CD jacket-leaflet, with a rich image - which can be downloaded, printed and inserted into the CD case.
These are small things, but you should give your techie-salesman all the tools he wants!

And let the open source world - the blogs, chat rooms, etc - know when its available! )

Create an event - be heard!

Have a small , fun , 'tracking contest' that tracks the number of WinLibre adopters and their brand ambassadors.
Turn this into something big; let the whole of the  community - slashdot et all -  know ( and talk ) about it.
The next time a techie hands out a CD to his mom for Christmas, it should be a WinLibre CD. 

(The discussion here is restricted to the desktop-PC-everyday-user market segment and does not include the Enterprise segment.
We are talking about OpenOffice and its likes -- not Mysql,netbeans, etc. )

The notion of 'Open Source' is too closely tied to the  'Linux' brand .This mostly turns out to be a disadvantage.
The general understanding (among the non-technical community) is that if one wants to adopt/promote open source products , one has to switch to Linux. The high switching costs at the OS level (not monetary costs)  dissuade most people from making the switch. This approach (from the OS up) can be termed as the 'Bottom-up Approach'.

I feel that the open source community should adopt a much different, 'Top down Approach ' to increase adoption.
Do not try to push  users to switch OSes. Instead, promote open-source  brands at the application level.
Not many people know that GIMP exists for Windows. I have personally evangelized OpenOffice-Windows  and GIMP for Windows and Firefox to so many of my windoze-user-friends; and I know that they are now loyal users. This works much better than giving them, say, a Knoppix CD - I know that they are just not ready yet. When users are comfortable at the Application level, and can see apps that they recognise, the transition underneath to an opensource OS can be that much easier.


1. But, at the application level, opensource brands are almost non-existent (OpenOffice, Firefox, ....?? ). Products exist, but they are not brands (yet).

2. Unified Channels do not exist; each product has its own channels for distributing and marketing the products. One cannot achieve economies of scale with such a 'scattered' strategy.

( WinLibre  is a step in the right direction. They have the bundling right, but not the brand (yet). )

IMO, the need of the hour is a common marketing(backed by  a powerful brand)  and  distribution channel for Open Source software at the application level. Throw in support and revenue channels into the unified channel, and then look at how open source can kick some serious butt in the desktop PC marketplace.  

This interesting discussion came up at the lunch table some  weeks ago.

A teammate was telling us about his Mechanical Engineering Professor, who walked into class on the first day , plonked a curiously-shaped object onto the table and put forth a challenge :

"Those who can give me a satisfactory explanation of  the behaviour of this object will get full grades in my course -- no exams/assignments."

He then proceeded to spin the object on the table.
The object, Im told, rotated furiously  in one direction, slowed down ,wobbled for a while, stopped, and then,  as if by magic, started spinning in the opposite direction, picking up speed .

Now, I do not know if anyone actually won the challenge, but this kindled my curiosity. A few seconds of googling unearthed details about the 'Celt' or the 'Rattleback':

http://www.physics.brown.edu/physics/demopages/Demo/solids/demos/torque.html
"Its as if some unseen had is playing a cruel joke on the laws of Physics."

Now, it sounded VERY interesting, but I had to see one in action myself. Google told me that several plastic celt toys are available on the Internet, but the scientist in me  found this link more interesting:

http://www.flinnsci.com/Documents/demoPDFs/PhysicalSci/PS10440.pdf
"Make your own celt from an ordinary spoon"

Well, at least I tried.
Several bent and broken spoons later (I kinda felt like  Uri Geller for a while :-) ) I gave up, with no success.
I'll get back to it sometime, after figuring out (from the science page ) what kind of spoon is best suited for a celt-toy.

Have any of you tried this , with any success ?

The Laughing Buddha Blog
Jai's views on Technology, Art and Life

Why call it the 'Laughing Buddha Blog'?
The legend of the  Laughing Buddha derived its beginnings from a mix in Buddhist, Taoist, and Shinto religions.

http://www.public.iastate.edu/~paddler/bodhisattva/budlaugh.htm

Hotei (aka  the Laughing Buddha monk ), is often caricatured as a monk with a large protruding stomach & smile.
He stands for  happiness, good luck, and plenitude.

And no, I do not have a protruding stomach , but I smile (a lot) and could do with good luck and plentitude; hence the choice of name.

I work as a Technical lead in Sun's Solaris / N1 group (thats where the blog's 'Technology' views come from),
am interested in Art ( graphic design/cartooning/pastelling/advertising - thats where the blog's  'Art' views come from )
and, contrary to popular belief about techies  , have a life (thats where the blog's 'Life' views come from).

Im also pursuing an _MBA_ program  at the Indian Institute of Management , Bangalore, trying to specialize in Marketing (Yes , I am interested in  the Dark Side), so do watch out  I can say a _lot_  without making much sense :-).

I like all things Apple , religiously read my Slashdot every morning ,and believe that Sun is the best technology company on this planet to work in. If you share my views, (even if you dont) do come back.
I promise I'll make it fun.