10. Britney Spears, "Toxic"
Spears nixed the shock and awe of her Britney era and displayed a more settled, comfortable maturity on In the Zone, with single "Toxic" serving as the premiere example of her transition. The star transforms into a double-agent in the adventurous, sexy and creative clip that has become one of the most easily identifiable images of the pop princess. It's long-lasting legacy is not only a part of pop music as a whole, it has stayed with Spears through all her eras, with the star creating sequels to the clip in the visuals for "Break the Ice" and "Womanizer" later on in her career.