You can seriously fatten up sounds or create wild new sounds by feeding one of the outputs back into the input. Almost all sounds will sound fuller and get more bass, and if you crank the input way up you can get a really fat oscilation an you're in subbass heaven..
Oh yeah, and what's also cool is that the oscilation phase you get is reversed from the filter resonance phase so you can do nice things with resonance and it won't just only beep like most of the things you feedback.
If you haven't done this before try it out now, trust me
