The name says it all: it's a wheel that controls pitch. Actually, this new version of QuikQuak's pitchshifter has a Timbre wheel, too.
The inner rings of each move independently, indicating the resulting pitch/timbre. Tweak the Inertia, Smooth and Gravity knobs and the ring can be made to swing towards and oscillate around the target, for oddball vibrato and glissandos.
You can set pitch via MIDI notes, with an eight-voice polyphonic mode.
In use, Pitchwheel is immediately gratifying. The Timbre wheel gives a formant-shifted effect that's valuable on more than just vocals.
The MIDI mode is a real gem, enabling you to 'play' any signal or even harmonise it. Quality-wise, it sounds impressive and works well on full mixes and solo instruments alike.