Amit's Thoughts on Path-Finding - Online paper about path-finding, including the A* algorithm and a greedy algorithm. Implementation notes, precalculation, map representations, heuristics, applications.
ASCII Robot Soccer - Unix soccer-like testbed. Source code (C++ with curses and termcap), executable, and screenshots.
Chinook - Checkers program written by Jonathan Schaeffer et al.; play online. Publications, endgame database statistics, game records.
Command Forces Simulation (CFOR) - Battlefield command and control testbed and knowledge base. Publications, source code, documentation.
Game AI - Publications, predictions, source code, and quotes having to do with AI and artificial life in games; mostly commercial video games, some board and card games.
GIB Research - Bridge program written by Matthew Ginsberg. Results, publications, library of deals with double-dummy tricks for each trump suit.
Hannibal and Brutus - Othello programs written by Louis Geoffroy and Martin Piotte. Descriptions, results.
Logistello - Othello program written by Michael Buro. Publications, game records.
Machine Learning in Games - Review of research and implementations in Backgammon, Othello, soccer, and other games.