I have an interesting perspective on this. I live within 50 feet of several sets of high tension, extremely high voltage (order of 600K volts) power lines.

Thus, I live in an extremely powerful magnetic field. I have to run all my computer monitors at 60Hz in order to avoid the affects of the field on standard CRT displays -- running at other refresh rates you can see extreme deflection of the picture.

I have lived like this for 3 years. Never lost a harddrive or floppy.

The field the fan throws off is infentesimal compared to the one I live in, I would guess.

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