Some friends have a Vintage Jukebox. This thing is old^Wclassic.
It plays vinyl and uses core memory to store multi-play selections.
It got a bit of a knock and stopped working. Long story short, the gearbox that transitions the cradle from traversing to spinning records was stuck.
Mechanical repair was not feasible.
Add a RasPi, some speakers and an Arduino to interface to the selection switches and the Jukebox was resurrected!
A web-interface allows uploading of music files, as well as playing them. The real fun is walking up to it and pressing the buttons though
All the code and schematics are on github:
Not the most elegant code I ever wrote, but there was a deadline (Birthday party!) which was met.