What Kevin said reminded me of a hunt i had where a decent size buck walked up so close behind the tree i was leaning against that my heart just about pounded out of my chest. I was bowhunting and i never moved. unfortunatley he came from my left to right and behind so being right handed and turning to my right with a bow created shot issues for me and i never got one off.
It was a very cool experience having a buck come within 5 feet of me