Orxonox

Orxonox is an open source 3D space shooter game and game engine, developed as an ongoing project by students at ETH Zurich University.

The engine embeds a Tcl interpreter in each thread, which includes bindings to the C++ API and can be used for inter-thread communication.

http://a.fsdn.com/con/app/proj/orxonox/screenshots/69304.jpg

http://www.lgdb.org/sites/default/files/node_images/1257/2309.jpg