You can also pretty easily adjust hair color (or anything else for that matter) in the Materials room, by hooking one or more Color_Math nodes in front of the texture map and adding and/or removing color as you desire.  In cases where the base hair color isn't completely black, you can exert a lot of control over what color the hair comes out to be.  E.g. if you have middling blond hair, if you wanted it to be bright blue, you could add two Color_Math nodes between the PoserSurface window and the image map for the texture:
One set to Subtract, and take out all the yellow
One set to Add, and add in a large amount of blue (e.g. 175)

I don't think a lot of people do this for clothing or hair but I do it all the time, makes it a lot less urgent to go buy "New Styles for Soandso".

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