As already mentioned, I have this for my phone:
http://www.seidioonline.com/index.as...ROD&ProdID=797
and I love it. For me, while the rubber keeps it from sliding around, I don't have any problems at all with it fitting 'properly' into a pair of pants. And it's nice and thin, too. It's also easy enough to get off if you want to clean it (which I never have had to do yet), and it allows you to use the keyboard without having to do anything additional to it.