David R Hoover, Architect, NCARB

Here is a very cool miniHouse that can be connected to the back of your truck and set on site without a foundation: http://sustain.ca/ Plus, it is not a trailer, but it still qualifies as a Recreational Vehicle.

There is an interesting little house that was created to provide housing to destitute areas by BSB Designs and the link is located here: http://www.myabod.com/