Boss: (to employee) - Experts say humor on the job relieves tension in this time of down-sizing, Knock, Knock. Employee: Who's there? Boss: Not you anymore.
A man phones a mental hospital and asks the receptionist if there is anybody in Room 27 She goes and checks, and comes back to the phone, telling him that the room is empty "Good," says the man. "That means I must have really escaped."