This reminds me of the left hand buttons on the accordion (which play chords). They're arranged in the order of the circle of fifths, so you can instantly trans

This reminds me of the left hand buttons on the accordion (which play chords). They're arranged in the order of the circle of fifths, so you can instantly transpose to any key just by shifting your starting note and playing the same physical pattern - at least, until you run out of buttons at one edge or the other. It makes it much easier to play chords by ear compared to the piano (at least, for me).