TacticalSpace is currently a visualization for Einsteinian relativistic motion. I recently restarted the project after making too many large scale changes (going from SDL to OSG for instance). The UI still needs a lot of work to become equal to what I had implemented more manually before with SDL.
The visualization is pretty confusing, but as far as I know realistic. Selecting a moving ship makes that ship the current POV. The positions of other ships are shown with lorentz contraction for the relative motion, and also their position is shown as speed of light delays allow.
In Special Relativity, there is no unique general reference frame and no simultaneity. But for the purposes of simulation I create a special single frame, and the POV of other frames are generated using the perfect knowledge from that reference frame.
Linux (built on Gentoo)
OpenGL 3d accelerator (built on 6800)
OSG
OSG is pretty easy to use, but has no manual. Instead there's a wiki, which in general have pretty serious usability problems. There's also a high volume mailing list and the OSG creator frequently comments there.
Tools
Graphics
Wings3D
Control Systems
Octave
Scicos
Galactic North Patternjuggler page/blog