[mr_toad]

Back when I was at university the x servers on our terminals were not secured, and other people could open output on your terminal. A favourite was a program that sent cockroaches scurrying around the screen whenever you moved a window.

[throwaway744678]

Ha, ha! Same here... The classical joke here was to send an xkill command: next mouse click will terminate whatever window was under the cursor.

[vidarh]

My university got a bunch of SGI Indy's for cheap as a marketing ploy by the importer, and everyone could log in to all the machines. It became a lot of peoples first experience of the privacy implications of webcams (they had them built in) and taught a lot of people the value of paying attention to the privacy covers.