MCDaemon, a python tool to control your Minecraft server
Source code repository of the FreeOrion project
Create Minecraft bots with a powerful and high level JavaScript API
A free/open source client and automation tool for Ragnarok Online
Python MUD/MUX/MUSH/MU* development system
CTFs as you need them
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
Air traffic control tower and radar simulator (solo + multi-player)
PyCAPGE - Python Classic Adventure Point and Click Game Engine
Homebrew save management, editing tool and memory trainer for Horizon
Multidocument automation by templates - for sphinx, mkdocs, epydoc ...
A pygame music lib.