I learned half my Italian from jingles on Greek radio. One, repeated around Christmas time for years, said "MIGLIORI AUGURI from xxxx (brand of spaghetti)". It stuck in the brain. Ten years ago I happened to pop into an Italian restaurant in Amsterdam first thing on Christmas morning (don't ask), and the family that ran it were all gathered handing round presents. Without thinking I blurted "migliori auguri" to them. You guessed it - they came back at me with a torrent of congratulatory Italian, surprised at my mastery of their tongue!

Back to English: One I can never get out of my mind is for Penguin chocolate biuscuits, with fake stutter:

P-Pickup a Penguin
A lovely P-Penguin
When you P-P-P-Pickup a Penguin there's so much more to enjoy
It's bigger, and chocolatey, with chocolate filling too
When you feel a bit P-P-P-Peckish, what's bigger and best for you?
A P-P-P-Penguin!
When you feel a bit P-P-P-Peckish, P-P-P-Pickup a Penguin