I made this looping animation of a ball in a cup. The ball makes the wood bounce a bit. I posted this animation on reddit. A few people thought it was real and wondered how this was possible. That was a fun reaction to get.
Wait a minute for it to load (is 17mb). I tried several gif makers but or the files became large or cut of some of the final frames making the loop less smooth. So I just posted the whole mp4 here.