By the way, I currently have a few blue streaks in my hair. This is not a recidivist punk gesture, but an accident due to keeping "Ash Blonde" toner on my hair too long. You can't see it unless you get close and stare hard, which most people won't do.
So I'm not sure whether I am going to do anything about it. Aside from the silvery-blue strands, my hair looks pretty good.