Last Saturday afternoon I was watching a trainee on ground control, which essentially means that I was sitting there with nothing to do (Saturday afternoons are the doldrums). Idly looking out the window, I watched as a ground crew loaded a large black Audi sedan through the side cargo door of a KLM 747. Nothing particularly special about that; we see cars as air freight daily, although usually they're being brought in, not carried out. The ICC ramp (International Cargo Complex) often has some exotic cars on pallets sitting around; we've seen Ferraris, Porsches, Jaguars, and Bentleys, as well as some that none of us could identify.
The trainee and I wondered how much it costs to air freight a car. Not having any actual information, we reasoned that it must not be cheap; even a small car weighs at least a ton or so. Once the Audi was loaded, the cargo door was closed and the loader moved off, and I forgot all about it.
A couple of hours later, I was working Local and the same trainee was monitoring. KLM approached the runway for departure, and I began the coordination with the other Local controller because the KLM's departure procedure was going to take it into the other controller's airspace. All went well until right after I told KLM to position and hold on the runway. As we watched, the airplane started around the corner and then made a sudden stop. I was about to query the pilot when he announced that they needed to hold for an alarm. I called the other local to let him know that my airplane wasn't ready after all, and then took care of a couple of other aircraft. In the succeeding lull, I turned to the trainee and jokingly said "I'll bet you it's the car alarm on that Audi." We both snickered and went on with whatever else needed our attention.
It was several minutes later when the KLM pilot came on and said that they were now ready to go again - There had been a car alarm going off in the back!