This one cracks me up, taken from an auction for the Casio KA-20.
“I’ve bent this keyboard for your pleasure.
1 Glitch Switch
1 Switch to turn on photo cell, wave your hand or light over the sensor and it changes the pitch of the note or tune being played.
1 Switch that does nothing at this point, future use”
The rest of the page appears to be a word for word copy from the WarrantyVoid Tablehooters website. Last time I checked the proper citations of the site were required. If the seller is serious about making money on circuit bending I would advise to include some samples and not setting the BuyItNow at $150.00 for something like this.