The Optek Fretlight combines a standard Stratocaster clone with a light-up LED neck, making it easier to learn how to play the guitar or learn new songs. The Fretlight happens to be a MIDI guitar, too, so you can send signals to it from standard music applications, or even other instruments. That means your instructor could play a short riff, which would light up on your guitar. And with quoted prices around $600 or so, it’s relatively affordable (compared to other MIDI guitars, at least).
Product Page [OptekMusic via JoshSpear]