I've seen Windows Blue Screen of Death, stalled boot process or simply application error dialog on many big information screens in shops, airports and other places as well in other systems such as cache machines, airport self checking systems or photo print kiosk.
Today coming back from US on NorthWest Airbus A330 we got stalled Linux boot screen on the main display when we landed. This must be some older kernel as it was in pseudo text mode black screen with penguin in the top left corner.
It is always fun to learn what is inside of these closed systems via error messages they might throw up. Too bad you can't see if MySQL is inside the same way. In the Internet however you can frequently learn smaller sites are powered by MySQL when they print MySQL error messages to the screen in case of problems.