In October I was working on my truck. I was cutting something with my penknife when it slipped and came down across the base of the nail (OWW!). The knife had actually cut through the nail and it was only attached at the edges, but I had no pain or anything so left it to 'grow out'. After a month or so, one side became detached, but the nail was still stuck to the skin underneath, so I couldn't rip it off without loads of pain. I got an emery board and basically filed the surface of the nail so it wouldn't catch on anything (had to do this at least every other day). The nail has since came off and I am currently left with a nail that looks as if it has been very badly bitten, but it is growing OK, so I expect it to look 'normal' in a month or so.