KVEC is a command line tool that allows you to convert raster graphics to vector graphics. KVEC is designed for 32 bit operating systems and runs on Win32, OS/2, HP-UX, NEXTSTEP, Linux, IRIX, AIX 4.x, Macintosh and BeOS. Docs are available in English and German. The shareware version is available for 30 day trial.
EQUINOX-3D is a 3D modeler with a very fast, fully integrated ray-tracer. It features read/write support for COLLADA, read support for Radiance's .hdr image format, 3DS (3D-studio) file format read support, multi-texturing, custom-programmable texture mapping, bump-mapping with automatic texture-space tangents, the ability to zoom into a region with "fly-to", and more. It includes a full runtime-class framework and a core design that allows for the addition of anything from a physics engine to a fully integrated renderer from a plugin. It is faster and more memory efficient than many other modelers.
Tesseract Trainer generates a full screen, real time display of a rotating tesseract, the analogue of the cube in 4 dimensions. It also adds point textures, which give you a feel of what each of the eight faces are doing. There's a stereoscopic option which adds 3D depth to the projection from 4D. It also features music and numerous other options to play with.