A little tapping demo on an electric guitar equipped with the FSK-401 Sustainer Kit from Fernandes Guitars. Since the sustainer kits provides for infinite sustain, held notes (and even open ones, as evidenced by some of the feedback) will continue to ring until you release them.
This provides a great tool for that two-handed, Stanley Jordan style of playing, and in this demo, you can even see that root-fifth playing in the left hand to hold down the bass part while the right hand plays melody above.