I really love the idea of pitch-based effects, but I never find a use for them. So here's the 3 latest ones.
Boss OC-2, great condition, you know how this one sounds, if you want that classic sub sound, this is it.
Shipped in the ConUS, $60 SOLD!!! (it was MIT since a few are asking)
Madbean Lowrider (Pearl OC-7 clone) Octaver: -1, -2, +1 octaves, all separately controllable. True bypass. Internal trimpot for gain control of +1. Bigger (and IMHO better) range of sounds than the OC-2. Letting it go cheap as it can make an audible pop when toggling the effect. Still very usable and sounds great, and probably an easy fix.
Shipped in the ConUS, $70
Behringer US600 Pitch Shifter/Harmonist. A million+1 different pitch effects. I believe it's a clone of the Boss PS-5, and some people like it better. Also takes an expression pedal input. It's digital and has the legendary Behringer mojo, so you really can't go wrong! 
Seriously though, you wouldn't leave it on all the time, but for wild effects, it's pretty cool, not even taking the price into account. This guy is brand new, never even been to a rehearsal.
Shipped in the ConUS, $25 SOLD!!!
Madbean Lowrider (Pearl OC-7 clone) Octaver: -1, -2, +1 octaves, all separately controllable. True bypass. Internal trimpot for gain control of +1. Bigger (and IMHO better) range of sounds than the OC-2. Letting it go cheap as it can make an audible pop when toggling the effect. Still very usable and sounds great, and probably an easy fix.
Shipped in the ConUS, $70
Seriously though, you wouldn't leave it on all the time, but for wild effects, it's pretty cool, not even taking the price into account. This guy is brand new, never even been to a rehearsal.Shipped in the ConUS, $25