Published on Dec 8, 2013 Dennis Kayzer
via this auction
This one obviously falls under guitar synth effects. I thought it was interesting enough to post at least once. Note this is not a vintage item.
Full auction description follows:

The Great Divide is 100% analog – the circuit tracks incoming audio and subdivides the waveforms to create lower notes at varying intervals. The lower voices are monophonic, but can sometimes be coaxed into tracking double-stops (say please!). The GD’s Upper Octave voice is a form of harmonic distortion that can track polyphonically with eerie precision and often unpredictable results (ring mod, anyone?).

Make your guitar sound like a Bass; an Arp; a Harp; a Hammond – whatever. Make your Bass sound like a Moog; a Guitar; a Moog Guitar or an asteroid hitting the Earth’s atmosphere – you get the idea…
For even more tonal options, patch in an external pedal via the TRS effects loop and control it with the Great Divide! OR, use an expression pedal to control the GD’s output level for gorgeous Synth pad volume swells and other assorted mayhem.
WORDS SIMPLY CANNOT DESCRIBE THIS PEDAL – Watch the videos and see for yourself, but please note that these samples are just the tip of a Titanic-tanking iceberg of tone. Now –GO GET SOME!!!
CONTROLS
The Great Divide features the following controls:
Dry Level Fader
-1 Octave Level Fader
+1 Octave Level Fader
+1 Octave Envelope Switch (sort of like Synth resonance, or maybe a cosmic death-ray)
SUB Level Fader & Switch with 4 Selectable voices ( -1, -1.5, -2 or -2.6)
SYN Level Fader & Clock with 5 Selectable Voices (0, -1, -1.5, -2, -2.6)
SYN waveform switch w/4 options (Saw/Pulse, Chopped Saw/Pulse, Square, Modulated Square)
Cross-modulation option for -1 OCT (tracks SUB clock)
Raw clock option for SUB voice (think MASSIVE, vulgar square wave)