Courtesy of a link at Miss K's place, we find this very interesting video of a group of friends building their dream in the hills of Washington state. The music's nostalgic, the fun they're having is obvious, and everything's laid back. I enjoyed it. Watch it in full-screen mode for best results.
I wouldn't want to live in a tree house myself, but a cottage on one of those headlands . . . that might be very nice indeed.