Just to keep updated, the GuitArduino is close to "completion". The only thing left to do is add all the guitar chords and scales. I spent the past 3 hours trying to improve my algorithm for loading scales, but I am discovering that the Arduino's clock rate isn't fast enough for it. I am trying to avoid having REALLY BIG ARRAYS but that might be unavoidable if I want the lights to appear non-flashing. The goal is to have this finished by the end of the weekend.