http://blog.wired.com/gadgets/2008/09/natural-materia.html

I found this article interesting, it gives brief descriptions of "green" bike frames, one mtb frame made of bamboo, and a road bike made frame made of carbon fiber infused with an ancient woven fabric (brain fart: I cannot recall the name).

Are bikes not green enough already?

It's more about using alternate materials to create high end frames.  The word green is just a selling point these days.

Those are cool and interesting.  While the production is less harmful to the environment, the irony is that most people will put those on their bike racks and drive them to their riding destinations.  I love me some cycling, but not to be environmentally conscious.