chain simulator: can you do it?

Miscellaneous Forums/Blitz Showcase/chain simulator: can you do it?

I made this "chain simulator" some time ago...

http://radicalrebound.com/chain.exe

i.e. there are a bunch of balls linked one to each other, and you can grab one (clicking the mouse) moving all the chain.

It uses a really neat trick to do the physics (which otherwise are really a mess), the code is 280 lines.

I'm not giving the code away yet: can you do something similar?