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Besides showing off her newly brunette locks, Britney Spears models another accessory – a Star of David necklace – as she and new guy Isaac Cohen (not pictured) leave Hollywood's Chateau Marmont Monday night. A source close to Cohen tells PEOPLE that the necklace belongs to him.
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Sienna Miller does the shimmy shake in a vintage dress at the New York premiere of her film Factory Girl on Monday. "I love the clothes!" the actress told PEOPLE about the movie's '60s-inspired wardrobe. "I haven't actually gotten to keep any yet, but I'm working on it."
The Factory Girl star later attended the movie's afterparty in her bloomers – what a minimalist! Weigh in on her daring look on our Off the Rack blog.
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DINE & DASH
Nicole Richie catches up with best friend Paris Hilton over dinner at Mr. Chow in Beverly Hills on Monday. They must have had a lot to talk about: Earlier in the day, Hilton filed a lawsuit to recover personal items, including risqué videos, that have been displayed on pay-per-month Web site Parisexposed.com for the past week.
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The laughter starts on the red carpet! Comedian Ant gets a foothold on Desperate Housewives star Teri Hatcher during a comedy event to benefit the AmberWatch Foundation in Hollywood on Monday. Hatcher is the national spokesperson for the foundation, which provides education about how to prevent child abduction and molestation.
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THE SINGLES SCENE
Hilary Duff enjoys the L.A. nightlife with sister Haylie on Monday, where the duo held court at hot spot Hyde Lounge. Since breaking up with Good Charlotte's Joel Madden last year, the singer says she's enjoying the dating scene, telling Ryan Seacrest on his radio show, "I kind of feel like a guy, like I can do it now."
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Kevin Federline, who has been getting flak for his new Nationwide Insurance commercial, takes it all in stride as he leaves New York City nightclub Butter Tuesday morning.
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A DAY AT THE OFFICE
After a day's work, Brad Pitt makes a shady exit from his West Hollywood office on Monday. The Babel star, who is currently filming The Mysterious Case of Benjamin Button in New Orleans, has been in L.A. to mourn the death of partner Angelina Jolie's mother Marcheline.
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Underneath that Cousin It-like hair is Liv Tyler, who looks happy to return to work on the L.A. set of her new comedy Smother on Monday.
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BEACH TOWEL BINGO
Cameron Diaz continues to soak up on the sun Saturday in Hawaii as she begins week two of her island getaway. The actress was accompanied by pals including Kelly Slater (not pictured) on her sandy sojourn.
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While sister Jessica is busy hanging with John Mayer in Florida, Ashlee Simpson takes a singular approach to shopping in Hollywood on Sunday.
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Penélope Cruz can't contain her love for her best-actress trophy at the Goya Awards – Spain's equivalent of the Academy Awards – in Madrid on Sunday. And the Volver star has another shot at award glory: She's also an Oscar nominee.
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COLOR HER ADORABLE
While mom Heidi Klum goes for an au naturel look, 2-year-old daughter Leni shows off her feline makeover during a visit to the Stuart Weitzman boutique in Beverly Hills on Friday.
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HAT'S OFF TO YOU
Kate Moss gives a loving once-over to rocker beau Pete Doherty as the couple strolls near the supermodel's home in England's Cotswolds region on Sunday. Earlier, Doherty and Moss's 4-year-old daughter frolicked in a nearby park with their pup.
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Pals Selma Blair and Scarlett Johansson rock the Social House in Las Vegas on Saturday. The ladies – who have known each other since costarring in 2004's In Good Company – dined on Asian cuisine and sake before hitting the craps tables at Caesars Palace.
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TAKE A BOW
Sheryl Crow makes a bright statement at the launch of Revlon's Colorist, a new line of hair products in New York City on Monday. The singer, who has said she's gained greater clarity since her struggle with breast cancer, is the official spokesperson for the product.