A warning is in place here. The magnets are very strong!!! If your finger get stuck in between two magnets, it will hurt. Even worse is a piece of your skin (Yes, it happened to me).
You can probably think of other ways of using them, but I decided to use them as hanging devices for tools.
In that way you don't have to buy hooks; just make the device yourself by screwing the magnets in place (provided that you kept the metal part that the magnet was mounted on). It's also much easier to attach the tool, since you only have to get close for it to snap into place.
Another, related, application is to hang jars from the magnets (metal caps required, obviously). My experience was that 3.5 inch hard drive magnets work perfectly for this purpose, while the 2.5 inch ones (left in the picture below) are a bit too weak.
You might wonder why two of the magnets are blue... That's because I intended to use them for the bicycle dynamo I already blogged about here. The blue part is shrink tube, which I closed with electrical tape to protect the magnets from getting rusty. There! Everyone's curiosity satisfied (expect perhaps those who wonder why Star Wars LEGO is hinted in the picture of a grown man's apartment...).
