GZDoom is a feature centric port for all Doom engine games
UZDoom is a feature centric port for all Doom engine games
3D Procedural Game Engine Using OpenGL
Roblox Shader – Download on Any GPU
A free Chess program for Windows with a large set of features
MIT Licensed Open Source version of Torque3D from GarageGames
Real-time collision detection and multi-physics simulation for VR
A simple turn-based artillery game and also a real-time strategy game.