Grit Game Engine - The Grit Game Engine is an MIT-Licensed Open Source Game Engine that is highly scriptable via Lua.
Nimi Places - Nimi Places is a Windows desktop organizer that gives you the ability to put files and folders into customizable containers. The elements in the containers are represented as icons or thumbnails. Read more about Nimi Places.
Pygame - Pygame is a set of Python modules designed for writing games.
iCollections - Organize your Mac desktop items.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Zeplin - Collaboration app for UI designers & frontend developers