Ever have a problem with squirrels eating all the bird seed out of your bird feeder? Me neither, but I might buy one of these just to laugh my ass off. The product, sold on Birdquest uses a battery to rotate the feeder. Birds don't mind being spun at a certain RPM but squirrels do. I'm not quite sure how it detects the difference (probably by weight) but this thing is freaking hilarious to watch.