For the first couple of weeks after my new iPhone 5 finally arrived I was reluctant to put this wafer of magic-touched goodness in a case. It was so small, so thin, so lovely to touch.
However, once the bill came for the phone I realized that, aesthetics aside, not having some protection around a device that would cost hundreds to replace if I accidentally dropped it was risk beyond my wallet's ability to absorb.
The first case I've tried is the Snap Case from InCase, a fairly slim, good looking, hard leather case that gives some added protection to the iPhone. In fact, though it does add a bit of size to the phone, I like the texture, which makes it easier to tell when I reach in my pocket which was is front, and which is back. A thin, but (in the event of an accidental drop) significant lip raises above the screen, just enough to absorb some of the blow of impact. At $49.95 ($39.95, as of this writing on Amazon) it isn't cheap, but it does seem well crafted, holding the phone securely.
I can't tell you whether the case would keep the phone from cracking if dropped. Sorry,I'm not going to drop my phone to find out. It looks like it would certainly help over a naked crash. At least the case gives me a better grip on the phone, subtle cues that make its use easier, and even a bit of personalization and style.