Make:

Eric writes - "I invented and built the first Guitar Machine in Tucson in 1994 and since then have built three more versions, each time making it more playable and more portable (for playing on the street, in subways, etc...). The machine, often compared to a Rube Goldberg sculpture, consists of an acoustic guitar, a bass guitar and a cowbell all suspended in a copper pipe frame. I play all three instruments by depressing pedals with both of my feet. There are no computers or anything like that involved, it's all mechanical. The pedals pull strings that cause several different movements on the machine, strings get plucked, capo things go up and down, a golf ball hits the cowbell, the "Pretty Polly" doll dances, etc..." Thanks Courtney! - Link.