Microhouse "Smart Module" and other designs.

Microhouse is a Seattle based design firm, that according to their website, includes architects, landscape architects, and designers.  They specialize, as their name suggests, in small house designs.  They promote these designs as backyard cottages or ADU's (accessory dwelling units), and they range in size from 120  up to 1,200 square feet. 

Smart Module axonometric drawing

Tumbleweed Lusby For Sale On eBay

UPDATE:  BIDDING ENDED MARCH 28, 2011.

Check it out.  I met the woman who is selling this at one of Jay Shafer's workshops in NYC.  The house is finished and ready to move into.  Currently located about an hour from San Francisco, but able to be moved to the place of your choosing, or left right where it is. You can get all the details at the link below.

Tumbleweed Fencl in New York

Me on the front porch of the Fencl 

My photos don't do it justice, but the Fencl is a great leap forward in terms of a sense of spaciousness within a small footprint.  For those familiar with the Tumbleweed Epu, this is essentially the same floor plan, but with a small bump-out near the entry, and a vaulted ceiling over the primary living space.  This results in a small expansion of usable indoor space, which many would argue is a significant improvement all by itself. It's the vaulted ceiling though that creates the increased sense of spaciousness.
You can learn a lot more about the house in the pictures, and all of Jay Shafer's other designs by visiting this website: