A simulator for the dice game Zombie Dice that can run bot AI players.
A full blog article explaining how these programs work (and the rules of Zombie Dice) can be found here: http://inventwithpython.com/blog/2012/11/21/how-to-make-ai-bots-for-zombie-dice/
This is useful for beginner/intermediate programming lessons or contests. The API for making bots is simple, and it features a web UI for projecting a nifty display of the tournament as it runs.