Ok I have one. This happened today.
Got a 50 inch plasma industrial monitor on loan for evaluation on a job at work. It has been sitting there for about 4 - 6 weeks. Our tech has it set up in the bottom of its box standing up on the foam corner protectors. Numerous times I have asked him if he is sure it is safe. Well turns out it wasnt.
For no apparent reason other than it should have happened a long time ago, plasma falls over and meets the ground. Giant cracks across the screen. About $8g down the drain.