Open Source Solid Modeling CAD
BRL-CAD is a powerful cross-platform constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing for rendering & geometric analyses, network distributed framebuffer support, image & signal-processing tools.
An open-source Phantasy Star Online server for *nix
Sylverant is an open-source server for the Phantasy Star Online series of games by Sega, written primarily for Unix-like operating systems. Sylverant has at least partial support for most versions of Phantasy Star Online, from the Network Trial for the Dreamcast through Blue Burst for Windows.
Tao3D is a programming language for real-time interactive 3D
Tao3D is a programming language for real-time interactive 3D. It lets you easily create dynamic, interactive, data-rich presentations, small applications, user interface concepts, and more.