Is it sustainable to ride a bike to go to work? for sure, but maybe you can go over that and ride a wooden bike to go to work, there's no limit for a tree hugging hippie !
I heard about wooden bicycles, then I made a small research... and the result is way better than what I was imaginating! check this out!!
gota bikes (brazil)
DIY bike (maybe the best one!)
more stuff about this subject: wheel fanatik
RIDE OR DIE !