Stanley Jordan has some interesting ideas
for using effects on Tapping instruments.

That looks like a clip from a Stanley Jordan DVD I have. Much of it was a sort if question & answer session.

This is described as an 'Instructional DVD', well it is but not necessarily in the way you might think. He's not so much teaching you to play like he does (though there's plenty of demo action and hints to allow you to follow that path through you own study & experimentation if you wish) as showing you how he thinks about music, practice & performance. I for one found this very entertaining, inspiring and 'instructional'.