In my first job out of college, our cubicles were outfitted with magnetic coat hooks that had very strong magnets. I would occasionally take mine off the cube wall and distort the display on my monitor with it. I did this a little too much once and ended up with a permanently distorted monitor.
Oh man, I just remembered somewhere I worked with monitors with a Degauss button. It was really cool the first time you pushed it but then it did very little until enough magnet stuff happened to give it something to do.
