My current favorite commercial is the one where the two guys are throwing sticks up in the tree, trying to get something to fall down, and then a VW falls out of the tree...when I first saw that, I died laughing!
I loved that "mother of pearl" commercial! (The one about the teeth!)
My favorite commercials of all time are the hallmark ones...remember the one that the little boy gave to his big brother, and then told him to act surprised later? (I think the brother was going off to college)...that got me misty eyed.
One last one...as a little kid, I used to like those Cheer commercials...the one where the guy would be quiet and put different stains on the clothes and then wash it out in a clear bowl filled with some water and Cheer??? I used to try to do the same...till my mother or my grandmother found out!

(Can you say, SWITCH?!)