http://www.youtube.com/watch?v=HkHx0XZLLps
Robosquirt demonstrates Ableton Live 8‘s Looper, using it to lay down a rhythm guitar track.
Using the overdub function and the FCB to switch between Guitar Rig presets, you can build layers and harmony on the fly.
I'd love to use Looper with some piano stuff — so often I've seen it with stringed instruments with deep sustains, not so much others. I've been playing a bit but haven't figured out the works yet. Maybe I'll need a special foot pedal, too.