Our idea of an useful bay reservoir

[Shoggy]

As stated in the text we even put them directly at the housing of a harddisk and moved them around - nothing happened to the data.

To get some serious damage to the data you would need a MUCH stronger and bigger magnet. From the beginning with the floppy disks we learned that magnets are a no-no but times and technology have changed and current HDDs are (almost) immune against normal magnetic fields like from such a magnet.

edit: I would bet that the magnetic field of some pumps are more dangerous than these little magnets