Orange 3D, a game engine distributed under the zlib/libpng license, is an all in one solution, with IDE, level editor, 2d painter, 3d modeler, and possibly audio editing software all in one clean package, for free!
A minigame tournament engine that allows for playing games against other people across the internet. The project is in the planning/alpha. It only currently has an Line of Sight Chess Program.
pgame-engine is a framework that is proposed to manage the common elements of many videogames like maps, time, resources, unit, players, teams etc etc... this engine is configured with xml and python files