http://brlcad.org - http://brlcad.org
An Open Source CSG solid modeling system with ray tracing support for rendering and geometric analysis, network distributed framebuffer support, image-processing and signal-processing tools. |
http://rogcad.com/ - http://rogcad.com/
Keyboard driven modeling software which supports complex curved surfaces. |
http://www.le-boite.com/minos.htm - http://www.le-boite.com/minos.htm
A free 3D solid modelling software offering fast hidden line removal, topological functions, 3D geometric constructions, IGES support, shading, printing, hatches, and line constructions. |
Shapeways - http://www.shapeways.com/
Ships physical realizations in a variety of materials of uploaded models. Includes available materials, formats accepted, pricing, tutorials, and support. |
solidThinking - http://www.solidthinking.com/
Modelling software that supports NURBS, polygonal modeling, and subdivision surfaces, available for Windows and Macintosh. |