FlightGear Flight Simulator: free open-source multiplatform flight sim
A planetarium software that shows a 3D simulation of the night sky
Teach your students how to figure out tricky texts in any language.
The ECE is for creation and managing ED3+ED4 characters.
Retro Games in Gym
Chess Database Application
scriptable game engine with built-in support for 2D graphics and sound
3D .NET engine for Windows, Linux, Mac
Some tools for GW2
The IRC's Talking Robot
web cms for clans and esport related pages
MultiVice - is a fully customizable multiplayer modification for Grand
Pear3DEngine is a modern and modular 3D development framework
A GUI Level Editor for the Enigma Game
Cross-platform 2D game engine