Rhino, Rhino, Rhino! $200 student price, and it is by far the easiest NURBS modeler to get into. The tools are intuitive, and you can use their Flamino renderer which costs extra, or BMRT for free. It exports just about every format, and imports all formats but OBJ, but there is a freeware converter for that. Best purchase I ever made! I purchased two versions of TrueSpace (4 and 5) and I found the viewport navigation and primitives manipulation to be too weird to use. Rhino you just right-click to grab the view and slide it around... even in the middle of a construction command... and the scroll-mouse button zooms in and out, again even in the middle of a construction command. http://www.mcneel.com For Rhino http://www.exluna.com/products/bmrt/index.html For BRMT http://www.dream.com.ua/thetool.html for Shaderman