Else for Sketchup you have a cool another trick maybe not so powerful than the nurbs of Moi ;)
but by curiosity you can try this free funny thing ;) http://www.tensile-structures.de/index.html
---
Pilou
Is beautiful that please without concept! My Gallery
This sketchy plug is some amazing! Try it! :)
The ragdoll acrobat in the file example is very funny to use :D
All volumes can be painting or generic modified as normal volumes :)
And you can import any component inside a simple "physic cube" here a french Cathedral, the hide the "cube" and voila:)