The Misa digital guitar has no strings to strum or pluck.
Instead of strings it has a touch-pad that enables the player to instantly adjust the sound of the guitar by where he or she places fingers.
PC World says:
The Misa guitar is actually an advanced type of MIDI controller that is powered by a 500MHz AMD Geode CPU and runs Linux under the hood (but don't worry; you don’t need Linux to use the guitar).
The Linux firmware code is open source, which allows programmers to modify it to their liking.