I did a metal shake roof. I'm very happy with it. It is supposed to outlast me!

http://www.metalroofing.com/v2/lightbox/uploads/regular/2390.jpg

They didn't sheet my roof, they laid it on the old 1 X 4's. I believe they attach a 1 x 2 strip and then the shingle is nailed in to it sideways. Supposed to be good to 120 mph wind.