When a little amateur singing competition called "American Idol" hit the airwaves six years ago, few could have imagined the monster hit it would become -- let alone that it would spawn chart-topping superstars, Grammy winners and even an Oscar winner. Fan favorite Michael Johns may have been eliminated, but don't shed too many tears for the talented guy. You don't have to be an "Idol" winner to have a winning post-Idol career in music. And if he's smart, he'll take his newfound fame and run with it... just like these former "Idol" contestants did. Click through this slideshow to see some of "Idol's" greatest success stories.