08/21/2008 AT 06:00 AM EDT
, singing with her Devil Wears Prada
costar and pal Emily Blunt
during an impromptu performance at Hollywood hot spot Green Door lounge
. After spending most of the night having drinks and chatting at a table in the venue's "library" with Blunt, friend Teresa Michalina
and a group of male companions, the actress – sporting a striped white blouse, skinny jeans and heels – made her way hand-in-hand with Blunt to the jazz band. The two crooned their way through a duet, then Hathaway and Michalina played backup singer for Blunt while the audience clapped and cheered. The group finally left the near-empty venue a little after 2 a.m.
, chowing down on a healthy tofu scramble with veggie sausage and egg whites while having breakfast at Hollywood eatery Kitchen 24. The actress, who was clad in jeans and a baseball cap, chatted with a male companion as she sipped coffee.
, celebrating his 25th birthday (which is on Aug. 21) at West Hollywood lounge Coco de Ville. It looked like a scene out of The Hills
as the birthday boy took shots with Doug Reinhardt
and was later joined by BFF Frankie Delgado
and Lauren Conrad
, who arrived with new man Kyle Howard
and Whitney Port
. Though Conrad mingled with Brody and his friends, her focus was clearly on Howard. The pair held hands, talked closely and kissed throughout the evening. At 1 a.m., the whole crew sang "Happy Birthday" to Jenner as a huge cake with sparklers and candles appeared, and they toasted him with Dom Perignon before the party moved on to Delgado and Reinhardt's Hollywood Hills house.
and wife Steffi Graf
, arriving at the Flor de Caña party at East Hampton, N.Y., club Lily Pond. The couple – who had attended a benefit earlier in the night – "took one turn on the dance floor before they slipped back into their chauffeured driven car," a source tells us.
, feasting with pals at Brand Steakhouse at the Monte Carlo Resort and Casino in Las Vegas. It was a guys' night out for the actor, who dined on King crab scampi, Kobe beef carpaccio, sea bass, salmon, filet mignon and a host of sides, including lobster mashed potatoes and asparagus. After his mammoth meal, DiCaprio and his posse headed to The Bank club inside the Bellagio to work off all those calories.
, having a family day out with wife Ryan Shawhughes
and 4-week-old daughter
Clementine Jane in the Hamptons. The trio stopped into Indian Wells Tavern in Amagansett, N.Y., for lunch, and Clementine took to napping.
By DAVID CAPLAN, ALEXIS CHIU, JENNIFER GARCIA, MARK GRAY and JEFFREY SLONIM
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