I have heard a few times from random mixing tutorials on the net that a spectrum analyzer can help in the mixing process. Does anyone have any experience with using one for mixing? If so, how do you use it in the mixing process?

Right now I do all of my mixing by ear, but the thought of being able to visualize the different frequencies and layers that I am mixing seems like it could help by allowing me to see when I have overlapping sounds that "muddy" up the mix.