There's a fellow here in Eugene who once made the cover of the now-defunct Auto Free Times who has ridden all over the Best Coast on a bicycle RV. The sleeping quarters are made of 4" rigid insulation and looks like a large silver coffin. He says when it's 20F outside he sleeps without any sleeping bag. I first met him in the '80s down in Davis, CA, but I just can't remember his name. I haven't seen him for a couple of months, so maybe he has migrated south again for the winter. (I'll look for my old copy and try to get a picture up.)