Season 4 champion Carrie Underwood has cleaned up nicely from her Idol days, going from big hair and frumpy gowns to sleek and sexy.

If you block out his dalliance with emo-boy bangs, Season 2 runner-up Clay Aiken has come a long way from his spiky, geeky origins.

Perhaps no Idol hopeful has had as complete a transformation as Season 5's Elliott Yamin. New teeth, hair, style and everything have helped propel him forward.

Color her not purple, but utterly transformed. Season 3 champion Fantasia, aka the single mom with the giant voice, has indeed come a long way, baby.

Though she didn't make it as far into Season 3 as she should have, Jennifer Hudson would soon after burst onto the scene with a star-making turn in Dreamgirls, for which she nabbed an Oscar.

Season 5 runner-up Katharine McPhee has made strides not just in her singing life, but her personal life, too. After her debut CD opened at No. 2, she wed boyfriend Nick Cokas.

Kellie Pickler has come a long way from mispronouncing "calamari." This Small Town Girl went gold with the hit single "Red High Heels."

Kelly Clarkson, your very first American Idol, has turned into one of its biggest successes. Let's just forget the ill-advised From Justin to Kelly, OK

Simon once said that Melinda Doolittle should have won Season 6. Having shed the newsboy cap and glammed up, we predict great things for her, too.

Though his somewhat spastic dance style and gray hair immediately turned off Simon, Taylor Hicks has stayed true to his Soul Patrol roots and kept the salt-and-pepper (while spiffing up his duds).