I bought another toy recently. A “fun fly stick,” which is a static electricity generator. Here are two of my colleagues playing with it. The levitating object is some aluminized mylar, i.e. tinsel.
The low ceiling in my office makes it difficult to truly appreciate it, but does show some physics. You can see the tinsel collapse when it touches the ceiling and discharges, and then pop open again when it’s free. The charges on the aluminum repel each other, and spread out as much as they can in order to minimize their energy. That’s what we are taught in E&M, and it’s easy to see this with a deformable object rather than the canonical rigid sphere.
The tinsel does actually get charged (rather than having some induced charge distribution), which you can feel on the occasions where you get too close and it attacks your face. Not too much of a shock, though. I tried aluminum foil, but it’s too heavy. (foil = fail) Packing peanuts didn’t repel like I expected, but that may work better in drier weather. The tinsel targets are a bit delicate and I have empirical evidence that they do not stand up to the treatment of two/three year-olds.
This is an ad from ThinkGeek (not where I got this particular toy) that uses a little more free space.
My friend got me this for my birthday. It’s the coolest toy evar.
I once learned to make my own at an AAPT meeting. You can use that thin foam-ish envelope that comes wrapped around some electronic equipment and cut it into strips to use as the floaty thing – make it into a loop with tape.