This is the Lego Star Wars Organ by Builders of Sounds:
You turn it with a handle, and as the various figures pass under these hammers, they make music.
Here’s how the team did it: “We took the iconic Star Wars Main Theme, rearranged it and translated it into a matrix – the constrution blueprint for the organ. Then, we took the four most famous Star Wars worlds – Hoth, Tatooine, Endor and the Death Star – and built them on to the barrel, accordingly to the musical composition. When the organ is turned, the bricks touch mechanical sensors – these strike the keys of a built-in keyboard and play the Star Wars Main Theme.”
And here it is in action: