http://www.furaffinity.net/user/zordrak won my comparison commission auction long ago. There are loads of versions of this on my FA, but I chose to only post one here.
SKETCH: http://www.furaffinity.net/view/15179141/
COLORED SKETCH: http://www.furaffinity.net/view/15191748/
PAINTED SKETCH: http://www.furaffinity.net/view/15408025/
LINEART: http://www.furaffinity.net/view/15191707/
MONOCHROME: http://www.furaffinity.net/view/15217126/
FLATS: http://www.furaffinity.net/view/15217147/
SIMPLE SHADING: http://www.furaffinity.net/view/15408083/
CEL SHADING: http://www.furaffinity.net/view/15611342/
PAINTERLY SHADING: you're lookin' at it!
FLATS BINARY: http://www.furaffinity.net/view/15645279/
CEL BINARY: http://www.furaffinity.net/view/15698503/
CHIBI: http://www.furaffinity.net/view/15829591/
DINKLE (flats): http://www.furaffinity.net/view/15407936/
DINKLE (shaded): http://www.furaffinity.net/view/15407991/
Painterly-shading starts at $80 as of this posting! https://docs.google.com/spreadsheet/pub?key=0AtF28QIKHc42dG1sazBQM0ZRSURpdG1QaXctSzhjRkE&output=html