The more you think about this one, the funnier it gets. Short and sweet, a good one. A very tired nurse walks into a bank, totally exhausted after an 18-hour shift. Preparing to write a check, she pulls a rectal thermometer out of her purse and tries to write with it. When she realizes her mistake, she looks at the flabbergasted teller, and without missing a beat, she says: 'Well, that's great . . . that's just great . . . Some asshole's got my pen!'