To be honest, our cellphones are pretty pristine—except for Herrman's here. It looks like he was chewing on it or something. But I'll bet you guys can do better. Show us your worst in the comments.
I think I'm alone amongst all my friends in that my cell phones are always kept in good shape. Here's my secret:
1. put it in your hip pocket.
2. don't put anything else in that pocket.
3. don't use a fucking case, you don't need that shit. it just scratches everything up and makes it hard to get in and out of your pocket, increasing the likelihood that you'll drop it.