When I store my player in the trunk, I always have to remind myself not to place it near the subbie for the very same reason.

I remember the weird distorted colors I got on the sides of the TV screen whenever I placed the stereo speakers too close to it, proof enough that there was enough of a magnetic field outside the cabinet to disrupt the electron beam...If your speaker has a relatively heavy magnet, I would definitely have it shielded or find another suitable location for it. I'm sure that a laptop's HDD smaller size would make it very subceptable to data erasure from exposure to a strong magnetic field. I know that some people use magnetic fields to render HDD unreadable.