3D Web UI, Embed Web and Flash in 3D Games, based on WebKit
An open source skateboard games engine written in C# and .NET.
Pear3DEngine is a modern and modular 3D development framework
Open Source Virtual World and MMOG Development Platform
Phobos editor is a generic resource editing system.
C++ Game programming Framework
An extensible development framework for roleplay games.
Investigo - DX9 Performance and Debugging Toolkit
A cross-platform OpenGL based lightweight scenegraph library
Cross-platform 2D game engine
Game framework on top of Python, Panda3D and Twisted
A DirectX based graphics/physics engine
The Lambda-Engine is a cross platform game engine.
Make games with Lego-like building blocks