Years ago in school, maybe about 1992 or so, I managed to make xdm (X Display Manager) crash and dump me a root window by simply holding down a key until the buffer ran out. I remember wondering how anybody didn't discover this before me. Similar behavior with the university phone system (repeatedly pressing '0') eventually dropped me an outside line that I didn't have to pay for (yes, for you young folks, we used to have to pay for long distance phone calls, on phones that didn't fit in our pockets).