use ambient occlusion as well.
1. setup some objects like a floor, a wall and window, etc.
2. make raytraced materials that are default grey, simple
3. make the diffuse color (Ambient/Reflective Occlusion)
4. choose the base color itself for that AO
5. add to some objects differently, voila.
now you can ALSO add lighting to the scene if you have to for dramatic effect.
maybe even add one or two levels of final gather (too much time usually on two)
render away. beautiful object reliant on the geometry and maybe the bump or displacement mapping
