Where is the prefab Henry Ford?

Bill Kratz made a heartfelt comment on yesterday's Comeback Cube post pointing out that the comments on the Apartment Therapy piece about Dwell on Design all dwelt on the most basic issue of all when it comes to shedworking - affordability. "No-one has yet realized the promised cost advantages of this approach. Where is the Henry Ford of prefab?" asks Bill. "A shed is the perfect laboratory to work on this problem. It is a microcosm of a somewhat larger structure suitable for living, but is simple and inexpensive (I know, I know, this is relative) enough for realistic experimentation."

Are shedworking structures overpriced? Or do they actually reflect good value for money? I'd be very interested to read comments from shedworkers and garden office suppliers/manufacturers on this issue.