C-Lesh is a game programming language for 2D games.
An extensible development framework for roleplay games.
C++ Game programming Framework
DiaT is a Textadventure
Cross-platform reimplementation of AMOS BASIC (runtime)
The classic intelligent role playing game
Game framework on top of Python, Panda3D and Twisted
also download updates from files section
Make games with Lego-like building blocks