Sometimes, when I bump into someone I know, and I am a little surprised, instead of saying, "How's it going?" or "How are you doing?" I accidentally say "How's it doing?" It is usually pretty embarassing, but there is the rare occasion when the other person responds, "Hey, how are you going?" in which case, we both sort of smile, and then pretend that we never even ran into each other.
Of course, for some people, I just skip to the last step.