I've beat the crap out of N900 before I finally got an Otterbox. It held up fairly well with only a couple little knicks on the right hand side of the screen and a couple of VERY light scratches in the middle area.

I've dropped it numerous times and even left it in my pocket for about 20 minutes playing some football in the park.. fell on it and remembered it. It took a pretty solid beating then too.

It's tough indirectly. But now with the Otterbox I think it's damn near indestructible.