Electromagic
Ever since last July, when I bought this magic wand, I've been dying to use it, now at last I'm doing electric fields with my first year classes. I almost forgot that I had it so they almost missed a big treat. I'm not sure how it works but it probably some sort of piezo electric device like a cigarette lighter. A piezo electric crystal become charged when it's squashed, when I press the trigger something inside starts clicking and the wand gets a static charge. The wand comes with some very flimsy Mylar shapes which when charged repel themselves into spheres like the one in the photo. To get them to this state is a bit tricky as they tend to stick to the wand, a quick flick and they drift up into the air repelled from the wand. I'm not sure how long this will keep working since once used the Mylar strips are impossible to store flat so after a while it will need some real magic to get them aloft. Today was quite a day for demos, not only did I get out the magic wand but I did a repeat performance of the hairy hand and got a student to try the hairy lip (you don't expect me to put magnets in my mouth do you?).