I have yet to spend the night in a hammock, but I did pick one up recently. After perusing this forum a bit, I decided I wanted a couple of carabiners and some webbing. So I went to my friendly neighborhood REI and picked up 2 biners and some very cheap webbing: http://www.rei.com/product/380043 I figured at 3 bucks a pop, if they didn't work I could use them elsewhere. I cut off the buckles and tied a bowline on both ends, then hung the hammock from them. They seemed to hold just fine, but it wasn't more than a few minutes. Is this a bruised bum waiting to happen?
Also, I don't understand the advantage of looping the webbing through a biner against the tree instead of running the webbing through its own loop; any light shed on my ignorance is appreciated.