As a programmer, I've become very interested in the board game Arimaa due to its origins in the world of Artificial Intelligence. The simplicity of the game means that people can pick up the rules quickly and learn to play very well, while the sheer number of moves available at any one time means that computers play it very badly. You can play Arimaa with friends using a standard chess set, but it's more fun to play with animal-shaped pieces like these.

This contains a pre-spaced set of 1 elephant, 1 camel, 2 horses, 2 dogs, 2 cats, and 8 rabbits. You will need to print out two sets (Preferably in different colors) to play. At this point you will also need to supply your own board. I have one in the works, but it is not ready just yet. The pieces are all about 1.1/8 inches square and should work with most standard-sized chess set boards.