Ditto on the hammock. For staying away from bugs it's the best. When it's cold weather, I don't mind staying on the ground under just a tarp, but hot weather the ants (and ticks, and other creepy crawlies) have free access. I got bit a couple times by ants. Not terrible, but not pleasant either.

One thing though... if you keep your backpack on the ground during the night, make sure you brush it off before putting it on! <img src="/forums/images/graemlins/tongue.gif" alt="" />