Absolutely marbleous!

https://www.youtube.com/watch?v=IvUU8joBb1Q&feature=share&fbclid=IwAR2y8TwYIScXGZuqYQ2M_wTxCklKAvWpxKiCj3M14HLG0POPwgveWS-4rY0

Wintergatan Marble machine - uses 2000 marbles to create music

For those of you more technically minded here is another musical link where it describes ratchets, pistons, crankshafts and demagnetised wheels in the comments

https://www.youtube.com/watch?v=1AEvQAg6TE0