With a bit of imagination, everyday objects can be turned into intriguing machines. A maker that goes by the name BanjoWise has created a fun, Raspberry Pi powered drum kit. BanjoWise says "Most of the drums are made from items I have found, or would otherwise have been discarded, including a fishing net from the beach, an empty beer bottle, and parts of a piano rescued from a neighbour’s skip"
"The internals are quite simple: eight solenoids triggered by a Raspberry Pi via a relay. To make the project interactive, I created a browser-based step-sequencer. The sequencer is available on GitHub, so you can build your own junk drum machine or modify it to fit your needs. Be sure to check out the video".
If you'd like to make your own Junk Drum Machine, there's a detailed guide on Instructables.com