1. I'm reminded of an Elton John concert I went to years ago. He was laying on his stomach, under the piano, playing with his right hand, and had his head propped-up with his left hand - looking at the audience. (And was playing well!)
2. When I was 10 years old, my parents took me to see Earl Grant play at a night club. (Had to get permission from the owner). Mr. Grant did a several minute long tap dance on the pedals! And the music was fabulous! I've never seen or heard of anything like it since.