A dead simple 2D game engine for Go
GemRB is a portable open-source implementation of the Infinity Engine
computer opponent for the board game Blokus
INSTEAD - Simple Text Adventure Interpreter.
Cerberus Content Management System
Free 32/64/16-bit multi-platform Pascal and Object Pascal compiler
A cross-platform interpreter for many point-and-click adventure games
Very Powerfull Crossplatform Qt Based Music Note Editor[Still Planing]
Java based Open source Voxel Engine for RTS games