The gTar is a really cool guitar teaching tool which uses a rainbow of LED lights under the frets to teach you where you put your fingers.
The whole thing is powered by your iPhone which snaps conveniently into the base of the guitar. Choose a song or a set of chords and the device will use the lights to show you how to play.
That alone is really neat – but the very clever bit of engineering is that on “easy” and “medium” modes, plucking the wrong string will not make any noise at all. Therefore if you play Twinkle Twinkle Little Star, that “twunk” in the middle of your song goes unnoticed.
$399 from www.incidentgtar.com