Upright piano's don't exactly scream "high-tech," since everyone's weird aunt has one. A pair of hackers from a company called MajorMega may change your mind, however as they've modified one to give you and your friends a fun way to create multi-part compositions. The "Quaver" upright piano is equipped with a Raspberry pie board that makes it act like a 4-track recorder and loop sampler. All you have to do is sit down, punch the big "record" button and bang out your part of the song. When you hit the button again, the piano will instantly play back your creation in a loop.
From there, your next friend (or a random stranger) can step in and repeat the process. Up to four people can add parts to the song, and when it's ready, you just hit "save and upload," to create an .mp3 file and store it on a special website.
To build the piano, the team used 1970's era Bose speakers, electromagnetic bar pickups and clever programming on the Pi. They also had to saw and drill the piano extensively to get everything to fit. It's now installed in a mall food court in Lancaster, Pennsylvania, and hundreds of users have already added short songs. Yes, there's a lot of Chopsticks and random plinking, but there are a few decent efforts as well.