Link here. Man, this just bugs the **** out of me. It happens to me constantly. When I'm on foot, I have started just turning around and walking the other way. This usually sends the idiot the message that it's time for him to go, and I'll take care of crossing the street myself.
If I'm driving, I usually resort to something I was told in defensive driving class a long time ago: look down and pretend to be messing with the radio.
If you see me and suddenly bring all traffic to a halt trying to get me to cross the street in front of you, I promise you I won't be the only one there calling you bad names.