There have been a lot of interesting sound design / recording posts recently from a variety of different reording blogs. There were two I really wanted to try for myself Hematite Magnets a la Erik Aadal (the shares and stock in these must have risen considerably since Erik's post) and a Hard Drive. I won't explain much about these as these two sources will do a much better job;
(Thanks for the inspiration!)
Having acquired some hematite magnets and a hard drive I set about recording both of them .... separately. I won't post the results here as if you have read the links above you will know what it will sound like.
Then I came up with an idea. Now like most people I have been told that putting strong magnets near electronics was bad, so with great abandon I started putting the magnets near and on the spinning hard drive.
What happened next was quite interesting.
Instead of exploding or electrocuting me the magnets created resistance on the spinning metal plate and slowed it down giving me control over the sound/pitch of the spinning hard drive.