I just bought a tent but wished I would have seen these first.
http://kifaru.net/TIPI.HTM
Holy cow. The best of both worlds. Ultralight and the "true outdoorsy feeling" of a hammock, but with the full coverage of a tent (minus the floor, which after having checked out the site for a while seems less and less important. )
The only problem is the price... but may be worth it. And the whole idea of having a totally portable and light wood burning stove in your tipi. So tight. Get the 4-man and put yer frickin' bike in there too! Alright, what am I gonna have to sell to get one of these? First of all, the tent I just bought...