Soundflower is one of those Apps you have always wanted. It allows you to route audio from one App to another. So let’s say you have Ableton Live and Pro Tools running on one computer. You are loving the way the scrubber tool sounds when you run it across a track (maybe the vocal since you are a big fan of Radiohead’s “Kid A” track), unfortunately, Pro Tools offers no way to record this down inside their own App. All you need to do is route Soundflower across to Ableton and record the sound into Ableton, then take the file and put it back into Pro Tools (possibly through Soundflower) and use it as you will. The possibilities are endless.