AfroDJMac has released Master FX Rack, a free Ableton Live rack feature effects that are useful for making song transitions and general song mangling:
I use this rack to do high and low pass filtering, add some reverb, bit crush the signal a bit, and put a subtle flanger over the mix for movement. It also has a control for a beat repeater, which is nice for glitches and stutters. And the final component is a combination high pass filter and delay. As you turn up that knob, the signal is simultaneously hi passed with a delay on top. Turn it all the way up and you only hear the delay and none of the original tracks.
See the AfroDJMac site for details and the download.