open source high performance realtime 3D engine written and usable in C++ and also available for .NET languages. It is completely cross-platform, using D3D, OpenGL and its own software renderer.
a simple alternative to the STL that includes multithreading and networking. `target audience' is developers of complex network daemons, robots or non-visual client/server applications of any kind.
a library to provide abstract access to various archives. It is intended for use in video games, and the design was somewhat inspired by Quake 3's file subsystem. The programmer defines a "write directory" on the physical filesystem.
a 3D Collision Detection and Rigid Body Dynamics Library for games and animation. It is an Open Source multiplatform C++ project. Discrete and continuous collision detection, integrated into Blender 3D and COLLADA 1.4 Physics tools support.