Links

Site Description
Battle for Wesnoth Wesnoth.org is the home of one of the shining stars of the free/open source gaming community, Battle for Wesnoth. In addition to the game itself, this site also hosts an active general open source game development forum.
BlenderNation A news site and forum dedicated to the open source 3D content creation suite, Blender.
DeviantArt Probably the biggest art community on the web.
FreeGameDev An Open Source game development site
Les Forges Les Forges is a pixel art website in French. Even if you don't speak the language, I highly recommend firing up Google Translate and reading some of their art tutorials, which are absolutely stellar.
OpenArena An Open Source first person shooter based on the Quake 3 engine.
OverClocked Remix A video game music remixing site. While not directly related to open source, it has an excellent forum for composers.
Pixel Joint A pixel art community.
Pixelation From their faq: "Pixelation is a message board about pixel art, first and foremost. Its role is to provide a setting in which people may sharpen their skills by posting work and receiving critique from others, and to offer critique when others...
The Independent Gaming Source Independent Gaming News
The Linux Game Tome The biggest and best portal for all games that run on Linux.
Toolkit Zone The official home of RPG Toolkit, an Open Source RPG maker.