I don't think the work of Dutch CAD designer Mark "Duckman" van der Kwaak needs an introduction on this blog. Most people will know his Cadbike 33 Beemer and he did the Cad work and developed the frame with adjustable trail, rake and seat height for Veon. The bike that was built by Krugger and winner of the 2010 AMD World Championship of Custombikebuilding. But here are some more of his Cad designs.
I really like his latest creation, inspired by Roth's Megacycle, but this version will have BMW power. Check his site for much more