A while back someone made a nifty little executable that when executed would create a duplicate of itself and then after a time execute the duplicate (I think it was 60 seconds or something).

The twist is that the program would have random chance of mixing up bits of itself when duplicating itself (mutating if you will). Some mutations would break the resulting executable rendering it 'sterile', some mutations cause the filename of the executable to be different than expected etc etc. The point is the mutation was pretty much random in what code it changed. This process would continue untill the computer froze after being overrun by thousands of little executables running and duplicating themselves every 60 seconds. All that was needed was a simple reboot and the system would be working fine again (albeit there would be a directory full of executables).

I believe the original creator found some interesting results after leaving his machine on for a while... some of the progranisms were in different directories, others had weird names, and a bunch of other stuff I'm probably forgetting.

I'd imagine a super computer would yield some pretty cool results...

Or of course, you could always do what I'd be tempted to do... Install WoW (using wine if needed) and then brag in trade channel about massive your computer is...