AI Wisdom - Attempts to catalogue every game AI article ever written in game development books, magazines, and conference proceedings. All articles can be searched by topic, genre, resource, or date. It's a very focused site and a great place to find out what secrets game AI professionals have published.
Game Development Search Engine, The - Web portal and search engine dedicated to game development. Links to articles, tutorials and source code that cover all aspects of game development. Read and post to game development newsgroups.
Game LS - The game development resource community driven database of sites, articles, multimedia. Forums.
Games++ Megasite - Game programming, online games, cheats, tutorials, references, Direct X, C/C++, and Java.
Games Research - Materials from, and links to resources related to, the Siggraph 2000 course "Games Research: the Science of Interactive Entertainment"
GarageGames.com - An online game development community and resource center, keeping independent and professional developers connected to their peers, the industry and cutting edge information, tools and code.
Gepard Studio - Downloads for game programming, along with some Java, Linux, DOS and Windows games.
GGD - Global Game Developer - Provides tools and knowledge needed to create and distribute games. Including tutorials, tips, downloads and books.