This would be a corollary to the previous Fanpost seeking the best event you've attended.
Mine was probably the Boston College vs. Syracuse basketball game in the Dome in '83 (?). Martin Clarke was playing out of his mind, sank the game tying shot with a couple of seconds left and drew a foul. Unfortunately, he missed the free throw, SU rebounded, and pushed the ball to Pearl Washington, who drained a running half court shot at the buzzer. I was sitting smack in the middle of the SU student section, with my best friend, an SU student.