1. CvuiA (very) simple UI lib built on top of OpenCV drawing primitives
2. opengl-demosA list of small OpenGL applications to demonstrate concepts of Computer Graphics
3. CodebotFree and open source (MIT license) web-based IDE focused on game development.
4. flixel-studioEmbeddable, in-game editor for HaxeFlixel. Turn the existing Flixel debugger into a full-featured editor!