What are your colour schemes and why?

I'm still trying to work that one out myself.  I find myself thus far using multiple monochromatic schemes within a project.  For example, I will take the individual channels for drums and percussion and make them all different shades of a color group (light blue, medium blue, etc), vocal takes various shades of red, and so on.  I match the buses to the color scheme for each group.  I try to make the dominant voice of that group darker.  I'm still tweaking it and deciding which color group works best in my mind for each category.