I remember a number of good ones. The first Bud Light commercial, with just the simple bucket of beer on the counter of the "remodeled" kitchen was funny.
I loved all the Doritos commercials. The Snickers one where Richard Lewis was whining, and the Rosanne started whining and got nailed by the log. The e-trade baby is always a hoot. The little Darth Vader that starts the car with his "force." The Bridgstone "reply all" commercial was great, especially for those of us that have lived through a "reply all" moment.
But there were stinkers too. Adrian Brody in the Stella (crappy beer) commercial was horrible. The old folks in the ECO commercial. The Kenny G one (don't even know what it was for)