On my way home last night I was following a Dodge 15 pax church van with a bunch of teens in it. The window on the single rear door was popped open at the bottom about 3". A girl in the last seat took what appeared to be a magazine subscription card, extended it out the window and let it go. The card slid UP the outside of the window until it hit the window/door joint, then it swooped back DOWN the window and back INTO the van.
She did it about 20 times before she got bored.