Been there, seen that.
No, there was a longer list I saw somewhere. I thought it might've been in the old 3.5 Rules Compendium, but it's not there. It had on it the DC for hearing a cat walk across the floor (DC 30, IIRC). It was a full page of examples like that... the DC to hear someone whispering, someone breathing, someone scratching an itch, and so on. (Okay, maybe that last one wasn't on there.)
Anyway, I'm looking for those types of examples...