Gideros Release version
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
A cross platform Lua based game engine
3D .NET engine for Windows, Linux, Mac
A generic 2D engine for any kind of game
3D Interactive sandbox environment
3D game engine for C and C++
Pear3DEngine is a modern and modular 3D development framework
The Lambda-Engine is a cross platform game engine.
Make games with Lego-like building blocks
A small Game Engine project.