Ze Text Adventure game Builder : Create as you play !
Molecular viewer and prototyping framework
Sdk library for creating 2048 game in c#.
2D Game Engine
Mad Vandal's FortressCraft Mod Source Code
Solve, explore and create Sudokus
XNA based game engine completely written in c#
this is tic tac toe or zero cross game(for windows os)
Open Source Virtual World and MMOG Development Platform
Fully fledged steam community SDK
2D top down arcade shooter