True story: I once drove from the main PX at Ft. Benning to buy a case of beer (carlings black label. . .mmmmm) and then returned to our barracks. As I was driving down the road it seemed like everyone was giving me the finger so I was flipping them off right back, the fuckers.
Turns out they were pointing at the case of beer I had set on the roof of the car as I unlocked the door. I didn't realize this until I got to the barracks and looked around in the car for the beer.
It was safe and sound on the roof. Air cooled to a lovely temperature.