Britney #6
Not long ago, most of the entertainment world had written Britney Spears off as a celebrity flameout. But over the last year Spears logged the fifth highest-grossing tour in the world, bringing in $130 million in gross box office receipts by playing 98 dates. High-profile endorsement deals with Elizabeth Arden and Candies' prove that the public expects Spears to stay in the spotlight for good.

Beyonce #2

One half of the most famous couple in hip-hop, Beyoncé continues to expand her business empire beyond music. Endorsement deals with companies ranging from Nintendo to L'Oreal and her growing House of Dereon fashion line bring in millions of dollars per year on top of the $86 million she grossed from a 93-stop world tour.

Lady Gaga #4

A newcomer to the Celebrity 100, Lady Gaga broke down the door to fame with outlandish outfits and quirky videos, including one that featured her and Beyonce poisoning an unappreciative boyfriend. Bringing in an estimated $31 million with a 106-date tour that grossed $95 million, Lady Gaga is also a marketer's dream, teaming up with Polaroid, Virgin Mobile, Monster Cable and Viva Glam.