Every time we go on vacation we get a few cases of water. We then end up with a lot of water bottles that have a kid sized sip taken out of them but no one will claim them. Generally just writing a name on the bottle does not work (it wipes off, etc). Does anyone have a cheap idea to mark water bottles? We used hairbands one year and that worked pretty well but with the other group we go with, we would need at least 12 different colors. It would need to be something easy enough for kids to do on their own and then keep track of. I was looking at can sleeves because then everyone could have their name and color but not sure if that is the best route. Opinions?