Jeffrey Lee Simons pointed me to two worthwhile ads in his posting "Admit It--You Love the Shamwow Commercial." The first is the Shamwow commercial itself, spawner of parodies, a zippy, simple ad that Simons himself says makes him want to call and chuck out the twenty bucks.
The other is a classic ad that I vaguely remember seeing before, one for music lessons. Here they both are.
The third I ran into looking for the Shamwow ad again on Youtube. It's long (four minutes!), but a good use of storytelling, and you can't tell what it's for until near the end.