Buy a package of metal coat hangers at the store. The hangers must be metal only - the metal ones coated in rubber won't work because they aren't reflective. This package of hangers must be attached together by a single plastic band around the hangers that can be moved down to one corner. This seems to be a fairly common packing method, so you shouldn't have too much trouble finding some hangers that are up to specs. You could always buy hangers that aren't packed right and strap 'em all together at the corner with a piece of string or wire, too.
Now, at your next party or other event featuring a strobe light (or alone in a dark room, for all I care), Grab one of these hangers and use it to shake the others around in front of the strobe light. The white light pulsing off the shiny metal hangers should make it look like you are juggling a big ball of lightning. The appearance is similar to getting a whole bunch of rapidly flashing sparklers and whipping them around and between and through one another really fast. You can get really creative here, grapping other hangers at random and whirling the whole tangle around whatever way you like - just be careful not to hit anyone! It's incredibly easy to get some very nifty effects this way, and it'll look to your audience (who, by the way, should not be directly facing the strobe light or it won't look nearly as cool) like you have madwhack ninja skillz. I discovered this completely randomly at a party six months or so ago. | 
