I don’t really think that the POG2+Big Muff thing would be (electronically) the most sense; combining a very low-tech fuzz with a complex digital octave unit would be kinda silly from a design standpoint. What I think would make a LOT more sense is a Green Wringer type mono octave up circuit.
Controls:
Octave
Fuzz
Filter
Filter Freq
Volume
Muff Switch
Octave Switch
Footswitch In
Clean & Wet Out

Atonal noise is fun. Deal.

Auto-tune is an instrument. Nothing more, nothing less. You can make crapy pop drivel with any instrument. When Jack Conte or somesuch uses Auto-Tune (The Giant), it can be very effective.

Also, http://www.youtube.com/watch?v=K3Xar3roRlY.

We couldn’t have these nice things without auto-tune, now could we?

Right, but that’s using filter modulation instead of pitch modulation. It might be repeating, but it would still be atonal. Which has its own appeal, but it’d be a very difficult-to-design box.

Wait, what if you had a vibrato with the LFO going through a S&H unit? That would get you close.

One Mr. Alex Lifeson might disagree there…

I have a DS-1 and its pure balls.

If there was a mix control on the Theory…

If only…