this isn't blowing a huge lead or anything but the 76 grey cup. gabriel wide open in the end zone. everybody in the building knew he was getting the ball and the riders still left him completely wide open. and he was injured so he was hobling around and we still couldn't cover him. CHOKE! (BTW i wasn't born until 85 so luckily ive only seen this after the fact)
as far as comebacks/chokes id say that houston vs buffalo in an NFL playoff game where houston was up 35-3 and the bills won in OT 41-38.
http://www.buffalobills.com/history/TheComeback.jsp