FlightGear Flight Simulator: free open-source multiplatform flight sim
An interactive viewer for three-dimensional chemical structures.
realistic driving simulation + functions for 2D/3D graphics
Java3d scenegraph editor
Tao3D is a programming language for real-time interactive 3D
Imagin Raytracer is a multithreaded command line raytracer
A simple and easy to use render farm for Blender
3D game engine for C and C++
Pear3DEngine is a modern and modular 3D development framework
https://github.com/horde3d/Horde3D
A C++ library to easily create GUI-editable objects
A simple web interface for Blender, for rendering animations..