I think this debuted during the Super Bowl 5 or 6 years ago. One of my favorite commercials ever.
YouTube: video
Damn. Time flies.i think it was first shown at macworld 2003.
I always had a fond affection for the "There's no Step 3" commercial. It really changed the way I personally thought about how something should work.
I did also enjoy the Yao Ming 12"/17" Powerbook commercial.
To be honest, I wish they'd go back to that style of commercial again. Cute, humorous, and "that makes you think" commercials have always been Apple's strong suit. The last commercial that pulled this off was the Air/Manilla envelope one. I wish they did something similar with the iPad 2 commercials. The current crop is honestly overly pretentious.
That has to be my favorite.