Lot 898 in the (canceled) Michael Jackson auction is a Mills Violano Virtuoso (on page 130 in this auction catalog). Henry Sandell invented this self-playing violin at the beginning of the 1900s. Metal “fingers” controlled by electromagnets set the notes and electric rollers play the strings. Many other mechanisms complete the device, keeping it in tune and even producing vibrato. There’s a player piano in there too for accompaniment. There are many YouTube videos of the Violano; here’s one of the double violin model playing Edelweiss.