Some photos of my first attempt at building a tricopter are in the gallery.
The tricopter is made from 15mm square wood struts with 2.5mm plywood top and bottom plates. Motors, flight controller etc. are from Hobbyking.
The tricopter is based on pawanvs99's article on instructables.com with a few modifications.
I was surprised at how well it flew for the first time as I hadn't set any trims etc. The first couple of landings were a bit hard but the only "damage" was that one of the ziptags holding a landing leg moved and the landing leg took a small notch out of one of the props (not even enough to affect subsequent flights).