Commodore 64 Bass Guitar!
Adam Rifkin stashed this in Guitars!
Sofa King cool!
It uses the SID chip and is based on an FPGA - a re-implementation of the Commodore-64 computer using reconfigurable logic chips. Ellsworth wears a portable amp and rocks the C64 Bass Guitar on roller skates:
She explains how she built it, with a Square Wave sound demo:
Or read this verge article for an explanation of what you're seeing.
I don't believe she's selling them, but she shows how she built it in the second video above.
In the past she has built such things as a Nintendo purse and a fire breathing furby:
She is best known for reverse engineering and designing the entire Commodore 64 audio and video system on a field-programmable gate array (FPGA). (She then managed to get it made cheap enough so it could sold on QVC!)
I bet she'd sell it to any of the guys from Devo.
That would be cool. Do those guys still play?