I'm old enough to have a LOT of favorites.
Successful commercials/jingles are, above all, memorable due to their impact on our human psychological traits and quirks. Cadence, beat, music, rhymes, visuals... there's a reason why there's an entire business devoted to advertising.
Without posting a link to give this away by the jingle, complete the words in parentheses to these jingles:
Five-eight-eight, two-three-hundred, (final word)
Or how about this one:
It's not nice to fool (final words)
Or:
I don't wanna to grow up, I'm a (store) kid.
And I have fond memories of Connie Stevens and Suzanne Somers singing:
(Store) is the place with the helpful hardware man.
Even if you're not old enough to remember these first hand, a lot of you will recognize them!
Probably the longest popular jingle/song i can remember was for the Slinky. The full song was a minute long, but most people remember the short version:
What walks down stairs, alone or in pairs, and makes a slinkity sound?
A spring, a spring, a marvelous thing! Everyone knows it's Slinky.
It's Slinky, it's Slinky. For fun it's a wonderful toy.
It's Slinky, it's Slinky. It's fun for a girl or a boy.
It's fun for a girl or boy!