This was on the radio awhile back:

A guy had car trouble as he was going out to dinner. He took the car to a mechanic, and they said they would check it out and let him know the diagnosis tomorrow. Tomorrow came around, no word, so the man went to the shop and asked about his car. The owner said:
"Yeah, sorry about the wait. The mechanic locked your keys in the car, he's out there working on it right now"
The man goes out back and sees the mechanic trying to jimmy the passenger door open with a hook. The man goes to the driver side and checks the door... it opens. The man says: "Hey buddy" and motions at the open door.
The mechanic says: "Yeah, I know, I got that one already" and goes back to working on the other door.
(True story)