I remember the game on Christmas Eve 2006 against the titans. It was the game where Robert Royal couldn't get 2 feet in the end zone on a trick play from Lee Evans and Vince Young killed us on a 4th and long scramble. Awful game, Bills lost by a point I believe.
Anyway...there was a happy group of titans fans walking out of the stadium to their car. One of them was a kid, probably 10 or so. An inebriated group of Bills fans proceeded to chases this group to their car, punch out the window and drag the driver out of the car. It was awful.
I feel like this kind of thing has decreased significantly over the years. Maybe its just me, but the crowds now-a-days seem more civil and less hammered.