Indie developer Digital Eel just released the source code of their game Strange Adventues In Infinite Space under the GNU Public License (GPL).

Although the source is written in C, sources for full games (like the recent source-release of ID's Quake3) are always interesting and especially since this source has been converted to now use SDL instead of Win32.

Note : Only the source has been GPL'ed, not the content (same as with e.g. Quake3)