Hi Michael

There was something about a plugin I thought for SketchUp quite recently?
Certainly other than ViaCad?

You may be interested in this about Blender Nurbs.
(A lot more info about)

http://download.blender.org/documentation/oldsite/oldsite.blender3d.org/117_Blender%20tutorial%20Fun%20with%20nurbs.html

Brian