I know Steve and Michael use very unorthodox techniques, and I'm sure that they have many little tricks up their sleeves that most people don't know about. For example, when I saw Michael live, I saw him do this weird thing where he would slap and strum in one motion.
I have a few little things that I fool around with, myself. After playing a note, I take my left hand off the fretboard, and use my right hand to make a harmonic. I'm also trying to find spots where I can make harmonics while keeping my left hand on the fretboard, which right now seems just about impossible. Another little thing I do, is when hammering off a note, I strum the strings below the string I'm hammering off of with my finger. Did that make sense? It doesn't always sound great, but I'm trying to master it.
I'll post some audio samples tomorrow to accomodate my post.

I think in your description you've hit on why these are seen as 'unorthodox' techniques - they're so damn hard to explain in print!

One of these days I'll get round to doing a DVD, showing everything I do, but 'playing nice tunes' is top of my list. :)

steve
www.stevelawson.net