I have a Zagg InvisiShield (www.zagg.com). Have one in my iPod touch too, it's great. Just be REALLY careful when installing and make sure you don't have any bubbles. I messed up and have a couple bubbles and they won't come out now so I will have to buy another and do it again.
Verizon offers a hip case that I was kind of opposed to getting at first. The belt clip doesn't swivel and it has velcro instead of a magnet. I guess some people are having problems with the magnet in the case triggering Navigation or Media/Dock modes. There was an internal Verizon document listing this problem that got posted on a Droid news site (sorry can't remember which one).
Anyways the "official" Verizon hip case is pretty good.