Hands down, it was like the first commercial aired. A beer, I think Budweiser? Two guys reaching for the bottle at the same time, then decide to rock, paper, scissors for the bottle, which they decide is fair. They call "1, 2, 3" and one guy actually throws a rock into the other guy's forehead, knocking him out. The first guy gets the beer and was like "I threw a rock".
I DIED OMG.
I also loved the Snickers one where the two guys pull a Lady & The Tramp and kiss, then need to "do something manly" afterward and rip out their chest hair and yell and stuff.
The Blockbuster online one with the guinea pig and the rabbit clicking the mouse was good, too.