MatCap (Material Capture), it is just a one time material that captures even the lightings and the shader of a material and apply it directly to your 3D model without needing of lighting setups.
I provided a wallpaper style tutorial,
(Click for full-view)
Pixologic MatCap Library
or watch it for more further info
Using ZBrush MatCaps in Blender from Kernon Dillon on Vimeo.