Mine is when people call down and ask about the "flashing light" on the smoke detector and a) if it means something is wrong, or b) if it can be turned off.
No and no! Don't these people have smoke detectors at home?
The alarm panel went off last night, and I called the room it indicated to see if there was a problem. They told me that the flashing was bothering them, and that they had disconnected it.
They were persuaded to hook it back up when I told them the fire department would probably show up if they didn't.