Comment by saghm

A roommate of mine in college used to leave his laptop unlocked all the time, and I found an app that would put an overlay on the screen that looked like a kernel panic. This went on for months, and he became convinced that his laptop had some issue where it would panic if he left it idle for too long. One day he happened to be going through his apps folder, and he saw something with a name like "iPanic.app", and watching his dawning comprehension as he realized what just must have been going on was probably the satisfying conclusion to a prank I've ever experienced.