This incredible LEGO grand piano has moving parts
Prepare to be impressed: While it doesn't actually play music, this 2,798-piece miniature LEGO model of a concert grand piano does have 25 independently working keys, a removable keyboard, and a height-adjustable bench. It also has a working damper and pedal, a self-playing mode, a working piano lid, and more. LEGO master SleepyCow engineered it to contribute to LEGO Ideas in the hopes that it will be voted in to be mass produced as a retail kit.
He writes:
Ever since I started learning music, I have always wanted to build a piano out of LEGO bricks. I have also been asked many times by my students about the inner-workings of a piano. I think this will be a great set to teach students about piano mechanics. I've seen many people do it in different ways, but I decided to make my own version, as well as try to make it as similar to a real piano as possible with correct proportions.