H'wood Party Girl

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Wanna know a secret? Even celebs who get huge paychecks love a deal...which explains why every star who isn't in the south of France for Cannes was at Barneys Thursday night.

Rogan Gregory's new eco-friendly line debuted at swanky Barneys in Beverly Hills before it goes on sale in Target. Fashionistas like Rachel Bilson, Becki Newton and Nicky Hilton were on hand to snag pieces, which are all priced under $44.99.

Marcia Cross confessed she's a Target regular. "I buy everything! I can't get out of there without a huge bill."

I asked the mother of twins if she had any advice for Angelina Jolie, who's also expecting two. "She can come over for a playdate if she wants to!" Marcia joked.

Whitney Port was also on hand, representing for The Hills and buying a bunch of clothes. Even though season three wrapped up this week, she told me the cameras are still rolling. "We've actually already started filming our fourth season," she said, adding that Audrina Patridge hasn't moved out of Lauren Conrad's guest house, as far she knows.

So does that leave any time for fun vacations? "I'll be going to Missouri with my family like I do every summer, but other than that, I'll probably be here working [at People's Revolution]," Whitney said.

Guess there really is no rest for the weary.

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Here's a Hint:  This A-list actress attending a New York premiere probably doesn't realize what she's revealing with every picture taken. But at least the new mom was smart enough to put on pasties before leaving the house.

Think you know who's got her headlights on display? Get the answer right here.

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While an expecting Angelina's been busy doing interviews, photocalls and junkets in Cannes, Brad's been on daddy duty.

Ange told reporters during a Kung Fu Panda press conference that her man was home watching their kids.

Well, they must have gotten a sitter, because the power couple both hit the carpet for the movie's premiere later that day.

Ange was glowing and gorgeous in a Max Azria Atelier gown, while Brad seemed to be growing out an unfortunate haircut from his latest movie.

To see all the stars making the scene in the south of France, check out our special Cannes photo gallery>>

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Snaps have just surfaced of Nick Cannon's surprise party for Mariah Carey at Six Flags Magic Mountain earlier this week. Check out those forced smiles!

As we reported earlier, the newlyweds rented the entire theme park Tuesday night for 100 of their closest friends and covered the place in lilac and pink balloons.

Mimi, who donned a bright pink Superman cape at one point, noshed on cupcakes in between roller-coaster rides with her hubby—which might explain the gritted teeth.

John Mayer and Jennifer Aniston have left steamy South Beach, but their relationship shows no signs of cooling. Last night, the two had dinner and drinks in New York City.

First, they had a cozy meal at the trendy Waverly Inn with three other people, where they sipped white wine, according to People.

Later, they headed to Hudson Bar and Books, where the couple stepped up their drink order to champagne and didn't hide their affection—reportedly kissing, hugging and posing for pics.

A happy Jen, who's usually press shy, even told paps on her way out that the date was "great, thank you." Could Mayer's media-friendly ways be rubbing off on her already?

Let's take a second to admire the work ethic of Kim Kardashian. Even on her day off from filming her first part in a movie, she still manages to hit L.A. hot spot Coco de Ville.

With sister/sidekick Kourtney by her side, Kim gives the public and paparazzi what they want: Instead of ducking in through a back entrance, Kim takes her time sauntering inside, ensuring every photog gets their money shot.

On her way out, she even stops to take pictures with fans before being whisked away in a waiting SUV. Seems the girl knows that to maintain the fame—achieved in part by her E! reality series—she's got one thing to tirelessly promote: herself.

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Update: Sources confirm that Nick Cannon and Mariah Carey celebrated their wedding Tuesday night at Six Flags Magic Mountain in Valencia, Calif. Only 100 of their closest friends, family and business associates were invited, including Mariah's manager, Benny Medina, Nick's father, and his half-brother, Reuben.

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Still no word of a honeymoon, but newlyweds Mariah Carey and Nick Cannon are planning a big blowout tonight.

A source tells E! News that the two lovebirds are renting all of Six Flags Magic Mountain theme park for a private party.

All the roller coasters you can ride until you throw up...sounds romantic! Guess these two really are "eternally 12 years old" after all.

And this is just one stop on their busy schedule: Last Saturday, they were at Ellen DeGeneres' 50th birthday bash and then hit Villa on Monday night for some drinks and dancing.

Coming up, Nick's jet-setting back to New York City to deejay at the Stoli Hotel soiree Friday.

No word on whether Mimi will join her man that night, but the way they've been attached at the hip lately, it wouldn't surprise us.

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Sex and the City: The Movie premiered today...but not in New York. Instead, New Line chose to hold the first premiere across the pond in London. (Where Sarah Jessica Parker attempted to blend with the shrubbery in an Alexander McQueen dress, Fred Leighton diamonds and Phillip Treacy hat.)

You'd think they'd unveil the film in the city where it all takes place, the one that's often referred to as the "fifth character," but no...the Big Apple viewing actually doesn't happen until May 27.

And if you're a New Yorker feeling annoyed that the Brits are seeing the movie more than two weeks before you, take heart: They're not premiering the flick in Los Angeles at all.

There is, however, a Skyy-sponsored screening here in L.A. the day before it opens in theaters, along with a postpremiere Q&A with Kristin Davis. You better believe I RSVP'd for that one months ago, so check back for all the details!

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Here's A Hint: This tiny tattooed actress was a child star who's still making movies. She usually leans toward independent films, but has a big summer blockbuster coming out this weekend.

Think you know who's sporting a tattooed torso at her Tribeca premiere? Get the answer right here!

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Following her second successful stint on How I Met Your Mother comes further signs that Britney Spears is working on a comeback.

Last night, Brit was on hand for the finale of MTV's Rock the Cradle, which her on/off manager Larry Rudolph produces. (The pop star stayed backstage during the taping and didn't take any photos.)

Later, she headed over to Sur in Beverly Hills, where she had dinner with another power player: George Maloof, who owns the Palms Casino Resort in Las Vegas.

Since it seems like he's willing to overlook her disastrous VMAs performance there last year, maybe a Sin City show wouldn't be such a bad idea for Brit?

Finally, Britney will get to spend time with her other boys, Sean Preston and Jayden James, on Sunday. She's reportedly been given permission to spend all of Mother's Day with her sons.

Flynet

Not only do Heidi Montag and Spencer Pratt share photo ops and a hatred of Lauren Conrad, they also use the same hairdresser.

After lunch at Cafe Vida in Pacific Palisades, the pair hit Piero in Santa Monica, where they got their locks lightened by the same colorista. Spencer had his hair done first, while Heidi waited and flipped through magazines...perhaps in hopes of finding a few pictures of herself?

Our spy says Spence ignored Heidi and texted on his phone the entire time. Apparently, his attachment to his iPhone is one part of the MTV reality show that's actually real.

Things are heating up between Jennifer Aniston and John Mayer since their steamy weekend in South Beach last month. According to In Touch magazine, John's planning to perform at the upcoming wrap party for Jen's new movie Marley & Me.

The soiree isn't until Saturday, but Life & Style reports the rocker's already back in Miami and shacking up at the Mandarin Oriental hotel, where Jen just so happens to be staying.

The party was originally set for Friday, but everything was moved around so her man could have plenty of time to prep for the performance. He's reportedly set to perform three songs at the Nikki Beach bash.

"It's hot and heavy, but in a very cool way," says a source. Sounds like it—even if the two aren't serious per se, Jen's getting some serious benefits out of being John's friend.