Hands down the 1994 NC vs. Miami. I was only 10 then and had now doubt through the entire season that we would win every game, even when Frasier went down with his blood clot. Ah, the unshakeable faith of youth.
Also the Henery FG and Suh INT vs. CU. I was watching it with CU fans - actually the person I was dating and their parents, and they all looked at me like I was crazy for getting so into the game the entire time. When that FG sailed through I just dropped to my knees as they all scowled at me. It was the perfect moment.