Colors and surfaces

Zbro's Matcaps:
http://luckilytip.blogspot.com/search/label/Matcap?&max-results=3#.WlFFgiOZPOQ
This is my favorite one for sculpting:
http://luckilytip.blogspot.com/2011/06/zbrush-matcap-share.html#.WlFGaCOZPOQ