Phobos editor is a generic resource editing system.
DiaT is a Textadventure
QuadTree JS is a library for game developers
cross-platform 2d game engine
CLM for Joomla! 1.5 + 2.5
A game engine in java for 2D strategy games
Java game engine for shoot 'em ups, using Java2D.
AS3 Utilities library (Games Development Framework)
A cross-platform OpenGL based lightweight scenegraph library
SDK for Resident Evil Games
Delphi-like IDE for cross-platform game development
Sourceport of the classic Descent Level Editor
A cross platform 3d c++ game engine
Game framework on top of Python, Panda3D and Twisted
Basic real-time simulation engine in C++
The Lambda-Engine is a cross platform game engine.