Well, I don't know about microtonic or whatever...but what I thought of when I saw the thread title was what happens to me sometimes when I play...I have bits of tunes come into my head, and if I let myself start playing them they just flow to a natural ending. These are tunes I've never heard before, and I never know if I'm playing the same thing over and over or if it's different every time; I never remember what I play and I've never recorded it. But I know it sounds good because I've done it in front of people.