A few months ago I created a new "keeps you up at night for the rest of your life" embarrassing memory, at work.
Customer had what looked to be a pretty decked out iPod Classic or perhaps iPod Video clipped to their belt. I like iPods, I've been off-and-on considering getting one for myself. So while waiting for their stuff to print, I make some small chat as I occasionally do. "Is that an iPod? That's really cool."
"Oh, no, that's my insulin pump."
"Ah. Sorry."