This doesn’t really have much to do with piano tuning per se, but a neighbor of ours, Scott Steffensen showed me this video (below) earlier this year. I was totally enthralled!
“The Chapman Stick (The Stick) is an electric musical instrument devised by Emmett Chapman in the early 1970s. A member of the guitar family, the Chapman Stick usually has ten or twelve individually tuned strings and has been used on music recordings to play bass lines, melody lines, chords, or textures. Designed as a fully polyphonic chordal instrument, it can also cover several of these musical parts simultaneously.”
(The above excerpt is from a Wikipedia article HERE.)