hydroslyder:
Wouldn't the magna clips completely screw your couple hundred dollar computer up, and also your watch if you got it close
Contrary to popular belief, magnets are not bad for computers in and of themselves. They may sometimes affect them briefly, but once moved away will not cause last effects.
They will however cause damage to magnetic media, such as hard disks, floppy disks, zip disks, etc. They may also damage CRT displays. This damage will cause data loss and can sometimes cause hardware damage.
That said, if there's magnetic media in your dive computer, you have bigger issues than a little magnet nearby!
Think of the last time you set it next to your computer speaker (because that's where the interface is) or it rode home in a bag next to the speaker in your SUV.
Magnets are all around us, and if you have something that is adversely affected by the smallest trace of a magnetic field, you have some major issues to work out.
I have never heard of a magnet causing an issue for a watch, though in theory it may stop the clockwork from moving while it is in close proximity.