When I was little I remember my mother telling my grandfather not to stand near the microwave because he had a pacemaker. I also was told not to look into the microwave because it would hurt my eyes.
Is that the reason behind your screen name? ;)
I took a microwave in to a repair shop once to get the door hinge fixed. The guy told me that in reality, microwaves only go straight and cannot bounce around to make their way through the door seal.
Even in my case with the loose door, it was completely safe because the door overlapped the opening. The only danger potential is with no door.