I remember changing a lot of nappies on trains. Who's going to be the first to think that trains don't normally wear nappies? We just spent a lot of time on trains when the girls were younger and they never seemed to wait until we were in a station or somewhere like that.
I've seen women doing that pin in the hair bit bit never realised why. I used to lick the damn things to make them slip through the layers. I figured a bit of their own Dad's spit wouldn't do any harm if I accidentally stuck one of the little darlings. (After all, it's family germs and all that.) Don't think I ever stabbed any of them, but I stabbed myself a few times.
We once had a pack of nappy pins which were so blunt they were dangerous. I sharpened them up using the little stone I used for fish-hooks. After that they were a treat to use, but my wife kept stabbing herself because she couldn't accept how easily they slid through.