50g shoot out of various Pi programs:
http://sense.net/~egan/hpgcc/#Example:%20%20%CF%80%20Shootout
Skip to the bottom if you want to see the winner:
http://sense.net/~egan/hpgcc/#And%20the%20Winner%20is...
Scroll down a bit on this link to see the 50g calculate Pi using Archimedes's 96 sided polygon:
http://sense.net/~egan/hpgcc/#Sidebar:%20%20P2F
Most of this is C code, but you don't need to compile the code yourself, you can simply download and play with the binaries:
http://sense.net/~egan/hpgcc/#Sidebar:%20%20Play%20First!
Edited: 14 Mar 2008, 7:48 p.m.