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.