[citation][nom]superblahman123[/nom]Magnets + anything computer = a pretty big problemHold a good sized magnet up to your screen and you'll see why that wouldn't work.[/citation]
Actually, you do it.  Unless you have a CRT, your screen shouldn't do anything.  LCD's don't respond to magnets because they don't work that way.
However, having a magnet close to a HDD, processor or motherboard i can see as a problem.  Some sort of shielding would have to be in place.
I do agree though that an air pump sounds a little too complicated.  Neat idea though.