Lately I've seen a few references to a mysteriously cool way of improvising based on foruths. Can anyone explain what this is all about? Just play some fourths? I fooled around with that, and found that if you stack fourths starting from a scale degree, you get a mode of the scale. I think the degree you start on + the mode you get will = 8. Is that a random useless fact, a useful fact unrelated to my original question, or something actually to do with this mysteriously cool fourths thing?