I did some painting to my case but it isn't a very professional job (just one/two paint layers).
I just sanded of the old paint of my case plates and then spray painted them. I also did this to the fronts of my CDROM and FDs. I used some modelbuilding paint to paint the moving CDROM parts.
But the paint layer is pretty thin and you can easily damage it this way... looks cool though.
My CPU runs so hot the arctic silver undergoes nuclear fusion