Andrew's Reversi game is pretty sweet. I think it could be really cool to play a game like that, but have people submit different AI's for it and play against each other. I don't think it would be too hard to have some standardized format and have people submit classes or something like that.
That could be a pretty cool CAOS event. Especially if you get professors to submit AIs too.
Actually, this might be easy to do. Since my AI just reports moves in an easy-to-output XML format, it would be easy to point the interface at another AI. If anyone is interested I can work with them on the logistics.