He suggested reminding teachers to take the belt out of their Van de Graaff generator and putting it into a ziplock bag. Store the bag in the top of the generator. Belts left in tend to degenerate. Dan Cahill asked how many people present electrical work and energy. He got several suggestions from lifting a weight with a motor to using a genecon.
Someone even likes to have the students run upstairs and measure their power.
If you convert to watts, the students can determine how bright they are. I failed to manage this but several people made nice little toys. I think the trick is getting the center of mass over the tip. Anyway it seemed there were several physics lessons involved here. Finally, Bob Stehman returned with one of those multicolored plastic slinkys.