Playing harmonica using an air compressor, solenoid valves and a micro-controller.
I did this machine during development of my entry to the Hackaday Prize 2016: <a href="https://hackaday.io/project/10302-high-speed-candy-sorting-machine" target="_blank">https://hackaday.io/project/10302-high-speed-candy-sorting-machine</a>
Yup this is hilarious and awesome. Well done! Now add in the rest of the notes!!