For me, personally, it would have to be one of my all-time heroes: Fred Jackson.
Fred 'Action' Jackson.
The offense went as he went.
Fred gave it his all every play. You could tell that by the way he ran. He didnt run effortlessly, but no one ran with more purpose than him.
He never went down without a fight. Refused to go out of bounds. And punished defenders at the end his of runs.
He would run into linemen and bounce off for a huge gain... Pull defenders another several yards.. He would even do a smooth spin move when you didnt know he had it in him.
Hell, he even had great hands!
Anyways, here is a link to some of his highlights. My favorite highlight is at 2:16 against the dirt bag patriots.
GO BILLS BABY!