I smashed my iPhone.
I don't believe in putting the iPhone in a case, I think that it diminishes the feel of the device. I simiply enjoy the sleek small feel of the phone au naturale. Adding a case, no matter how thin or small just makes the iPhone bulky and doesn't feel right.
Of course, without a case, the iPhone is a slippery device. as hard to hold as it is beautiful. I've dropped it about a half dozen times, including once on a tile floor from about chest-pocket height. Recently, I picked it up after a short fall to the floor of my car and the screen was completely shattered. Even though the fall was only about a foot and the floor of the car in my Honda Element is reasonably soft, it was just one fall to many.
The amazing thing is that even though the screen shattered like safety glass, it's still usable. While I do have some hesitation about sliding my finger over broken glass, it's works just fine. Even the recessed area with the brass button (the home button) still works!