As was reported earlier this week, id Software has open-sourced Wolfenstein: Enemy Territory and Return To Castle Wolfenstein. Opening up these older games under the GNU GPL was done as part of id's long-standing tradition of putting out the code into the public domain once it makes sense for them a few years after their succeeding engine updates have fully replaced them in the marketplace. The developers behind ioquake3, the project that's based around the Quake 3 engine that was previously opened up by id Software, is already working on iowolfet and iortcw forks to incorporate this new code, but other free software developers are already utilizing this code too.