Sometimes Laurie and I do stupid stuff -- like trying to match our arm movements to the beckoning cat in the living room. For some reason, it isn't very easy to mimic or catch the rhythm. I put fresh batteries in it yesterday and she was able to get a two arm version going. I doubt I will ever match such incredible talent.
This is similar to ours. (Sadly, the presented GIF-motion belies its smooth and fluid movement):