Armory is an open-source 3D engine focused on portability, minimal footprint and performance. The renderer is fully scriptable with deferred and forward paths supported out of the box. Armory provides a full Blender integration add-on, turning it into a complete game development tool. The result is a unified workflow from start to finish. Powered by Armory engine, ArmorPaint is a stand-alone software designed for physically-based texture painting. Drag & drop your 3D models and start...
Vitral SDK (Vitral Software Development Kit) is a java based software architecture for the development of computer graphics applications. Supports solid modeling, offline and JOGL rendering, animation/simulation and human-machine interaction.
ColladaLoader is a free open source C# Library that enables developers to load and display Collada 3D Model files (.DAE) in DirectX 10 using the SlimDX SDK. Partitial .X file support. More info: http://www.tomsdevshack.be/projects/colladaloader
An implementation of a virtual trackball in C# for use in 3D .NET applications. Depends on the presence of Microsoft.DirectX namespace (DX 9 SDK). Can be used with OpenGL with a translation from DirectX.Matrix to appropriate gl calls.
Javascript SDK for Nintendo Wii's Opera browser with classes for 3D vertex math, triangle meshes, canvas drawing, Wii Remote motion/button detecting, and multiuser interfaces. Official site: http://wiioperasdk.com and blog: http://blog.wiioperasdk.com.