a game programming library for C/C++ developers distributed freely, supporting the following platforms: DOS, Unix (Linux, FreeBSD, Irix, Solaris, Darwin), Windows, QNX, BeOS and MacOS X. It provides many functions for graphics, sounds, player input, etc..
Cosm is an integrated collection of extensions to Max/MSP/Jitter to assist the construction of navigable, sonified, complex virtual worlds, and has been designed to facilitate use in CAVE-like environments.
Espresso3D is a high performance real-time 3D engine for the Java(tm) programming language. E3D is not just a scene graph. It aims to be a complete solution for your application with OpenGL rendering, OpenAL audio, collision detection, input, and rendering support.
Espresso3D began as a free for non-commercial use library in October 2004. As of April 8, 2008 Espresso3D is available under the open source LGPL license.