UTPG

From UnrealAdminWiki

The Unreal Tournament Preservation Group is a group of programmers and server admins from the UT community who got together and approached Epic about the possibility of maintaining the Unreal Tournament code base. Their goal of maintaining the game and fixing obvious problems, while keeping all the major game-play systems 100% intact, were right along with Epic's goals, Epic granted UTPG access to the source which allows them to undertake this project. Their focus is general maintenance with some time spent dealing with security issues in the Unreal Tournament engine.

Homepage

http://www.utpg.org