While stationed in Okinawa, Japan, I heard about a stunt some radar techs did once. Getting hungry but no where to heat up their frozen pizza, they put a couple of wood dowels across the the inside of a microwave dummy load. Put the pizza on top of the dowels bolt the dummy load onto the wave guide, zap for a couple of minutes and the pizza was cooked.
Problem was shortly after they had managed to eat the 'evidence' a master chief wandered in and noticed the dowels in the dummy load. But could do little because the 'evidence' was gone, but not the smell which was carried through the building.
Though, I did get the feeling that it was not the first time the radar system was put to such usage.