Magnets near computers at all while we're at it LOL.

We learned to tolerate a big purple-green splotch in the corner of my family's ultra heavy CRT display after I held one of those neat telescopic-magnet-wands too close to it once.

Then I learned there was a "degauss" function!

That seemed like magic how fast it made the unsightly blemish, and my parents' irritation, vanish. XD

I remember seeing tutorials on making a neat degaussing contraption using magnets and an electric drill, too. O.o

Hard drives though...probably not as easily fixed.