This started as a small experiment on making a 3D bezier curve editor.See the blog post for more info. Binaries and some sources are kept here.
Timo Suoranta, firstname.lastname@example.org http://neure.ath.cx
Thanks to Vincent Tan. He discussed bezier curves in a number of blog posts, for example in Reverse engineering Bezier curves.
There are some known issues with the code above. I have not released an update yet, but here is a new screenshot with a NURBS curve and three shadowmapped light sources: