Improved Quake III Arena engine
A flexible, high-performance 3D simulator for Embodied AI research
Odamex is a free, cross-platform, modern client-server Doom engine
A free 3d game for PC that does not limit the player. Fight,Build,Gain
Source code of the chapters of the book 3D Game Development with LWJGL
A minimalist and cross platform System Shock source port
486 lines of C++: old-school FPS in a weekend
Easily convert to MP4 with H264 and without all the codec hassle
A ridiculous fast-paced fps campaign on the Cube 2 engine
Free and open source FPS based on Quake III Arena
Actionscript 3 Particle Engine for Flash and Flex