I am always fascinated by Serbs' ingenuity, and if you remember this other post of mine, you'll see what I mean.
I watched this fellow in Tasmajdan (Tash-MY-dahn) park the other day. He had attached an elastic cord to a tennis ball, and the other end to the rear (now in front!) of his baseball cap. He batted away, and while I watched, the tennis ball got him only once.