Yo yourself dumba**!
That's what a pedestrian said to me today as he jaywalked in my path.
He was looking down at his ipod (mistake #1) and jaywalking, crossing the street in the middle (mistake #2) with me coming at him (mistake #3) and I let off a quick "Yo!" to catch his attention.
So I did my best to keep my messenger poker face, didn't blink, didn't turn, stolid, put my left hand up and gave him the finger as I went by.