NEW WALLPAPER: Britney Spears in a Bikini!

The 27-year-old mother of two showed of her toned tummy at a photo shoot at the Ritz Carlton in Los Angeles Thursday.Late last year, Spears had begun intense training to ready for her worldwide Circus tour. Usmagazine.com reported she shed 20 pounds, thanks to two-hour cardio-and-strength-training workouts three times a week (on top of dance rehearsals).