Tower: "Airline XXX, it looks like one of your baggage doors is open."
Captain (after quickly scanning the FE panel): "Ah, thanks tower, but you must be looking at our APU door."
Tower: "Okay, Airline XXX, cleared for takeoff."
Captain: "Cleared for takeoff, Airline XXX."
Tower, during the takeoff roll: "Airline XXX, ahh ... it appears that your APU is leaking luggage..."