This magnetizer/demagnetizer tool is one of those things that, if you haven't used one before, will make you think, “There's no way that actually works” — but it really does. If you need a small tool (screwdriver, wrench, drill bit, tweezer, etc) or any hardware parts (screws, nuts, bolts, nails, etc) magnetized or demagnetized, you simply insert them into the appropriate cavity and voilà.

It won't make an object a supermagnet or anything, but hey, it'll help you get the job done when you need it. It's also real small/portable, plus it doesn't need a battery to do its thing. Comes in red, black, and blue.

Get it for $7 on Amazon.