Liquid is a tool for translating Maya scenes into another renderer's scene description. Various RenderMan-compliant renderers are supported. For more information please see the project homepage.
TerraVision is a real-time multi-threaded 3D terrain visualization system. It can browse massive terrain and other data sets that are streamed over the Web. It also supports overlaying rich 3D models on the terrain to represent buildings, icons, etc.
The Virtual Environment Software Sandbox (VESS) is a suite of libraries for developing virtual reality applications in a portable manner with classes for many tracking devices, a simplified "scene graph", a set of "motion models" and audio support. Please note that all support has been moved to GitHub at https://github.com/ucfistirl/vess.