I Forgot My Library Card

This afternoon at the Circulation Desk a gaggle of middle-school boys walked up with a friend who had forgotten to bring his library card - to the library. The library card barcode is required to log onto the public internet terminals; after school hordes of students race to log on to play computer games, er do their homework, I mean.
Middle-school boy: "Can you give me my number? I forgot my card."
Me: "Didn't you memorize your number? Or write it down on a notebook?"
MSB:  shakes head negatively.
Me: "Do you have a cell phone? You could program the number into your cell phone. I bet you never forget your cell phone." (That may be true, but losing a phone is quite common as our lost and found box will attest to. Can a box attest?)
MSB: "OK."
So I ask the boy's name, look him up in our system, quiz him ruthlessly on his home address to prove that this is serious business, and hand him his number on a slip of paper. He and his friends leave.
Before I can escape from the Circ Desk, another MSB comes up and asks for his barcode.
Me: "Weren't you just here with your friend?"
MSB: nod.
Me: sigh.
Lather, rinse, repeat.