For those not yet in this elite group -- no, it doesn't hurt. It's nothing like when you cut a nail too short and it bleeds and gets tender. As the nail loosened, the skin beneath got thicker. That area actually has no feeling. I say that, but the whole lack of toenail does feel incredibly odd!
I find myself wondering why it is that nails fall off. This was an incredibly gradual process -- starting months ago for my right nail and at the marathon for the left. And of all the times I've dropped things on my feet, tripped, banged into stuff, worn shoes that were too small... it takes running for long periods of time for this to happen? How does THAT make sense?
I think I need this shirt from OneMoreMile, though. If only it had a naked toe on the back... ;0)