I am looking to customize my system, making it look a little more pleasing to my eyes, and I know I have seen an article somewhere, but I can't seem to find it anymore, on how do I change the color of the close icon in Unity on 12.04? Does anyone know how I can do this, as well as change other system colors?
There is a tool called MyUnity that allows you to change color schemes and install any GTK theme you like.
http://www.uielinux.org/myunity/