Self-hosted game stream host for Moonlight
A free/open source client and automation tool for Ragnarok Online
Open source clone of the Age of Empires II engine
Code for Cicero, an AI agent that plays the game of Diplomacy
4X Space Strategy Game
GemRB is a portable open-source implementation of the Infinity Engine
Cooperative multiplayer graphical RPG and adventure game
Realism Invictus mod for Civilization IV
Opensource Created Custom Viewers For Virtual Worlds like SecondLife.
... the open-source glide computer
Vivid3D is a C++ IDE/3D engine, with python scripting.
GameServer is a sophisticated, game server designed for online games
Add and Subtract game
Janken - A Simple Rock, Paper, Scissors Game
Get your own sweet custom status for discord
DOOM / Heretic / Hexen source port with enhanced graphics and UI
Retro Games in Gym
Character animation system for games and simulations.