Maybe I've already done this one, but found this scrap of paper and had to share (again?).
I'm at the library. In the quiet, no cell phone zone, perusing the new book selection. This woman beside me is prattling on to her friend on her cell phone. I try to ignore her until she says in an annoyed voice to her friend:
"Hello! Presence of mind! Awareness of where you're at!"
At which point I gave her "You are one of the stupid people they warned me about" look.