Every part of this harpsichord, including the keyboard, is made out of Lego pieces. The only exceptions are the wire strings, which, if made of Legos, wouldn't function properly.
Here's the info on how it was constructed. It includes a ton of details. What's particularly amazing is how they managed to build a Lego structure that wouldn't fall apart after repeated play. There is also a link to an audio example of what it sounds like.
It's worth noting that other people out there have constructed smaller Lego Harpsichords (see the video below), so it stands to reason that a young engineer with enough know-how could put their own together.
Tomorrow's instrument is always putting its neck on the line.
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