This technique is a blend of harmonics and finger tapping and sounds pretty cool. It is not too hard to get down and it is lots of fun.
Make sure you check out TE-501 • How Harmonics Work too so you understand what is going on.
The Basic Idea
The basic idea is that you tap exactly 12 frets above any fretted note that you play. The video should set you right - it is all a lot more easily explained with video...