Plus: Nicole & Keith attend a Haiti benefit brunch, Penélope Cruz, Cameron Diaz and more

By People Staff
Updated January 26, 2010 06:00 AM
Janet Mayer/Splash News Online

• After taking a bow at New York’s Radio City Music Hall following a sold-out four-night stand, Lady Gaga hightailed it to 1 Oak in the meatpacking district to celebrate. The pop diva wasn’t suffering from a lack of energy: At one point, she shook up a bottle of champagne, held it at crotch level and sprayed the crowd, so even her date – designer Marc Jacobs – got doused! Sporting a skimpy black dress and shades, Gaga also chatted up the occasional fan and rocked out to the ’80s tracks playing (as well as her own hits!) before calling it a night with her pals just before 3 a.m.

• It was a who’s who of Hollywood at Paul Haggis’s L.A. home, where the Crash director hosted a backyard brunch to support Haiti relief efforts. Nicole Kidman and hubby Keith Urban mingled with guests like Charlize Theron, who was spotted chatting with rapper Ludacris. Nearby, Penélope Cruz and beau Javier Bardem hung out with Josh Brolin. In addition to an Asian-inspired breakfast sandwich with miso eggs and fried pork belly, guests enjoyed mini-French toasts, drinks and musical performances by Sheryl Crow and Jackson Brown, among others. Overall, the event raised $2.5 million for Artists for Peace and Justice.

Cameron Diaz, greeting each of her friends with a hug while hanging out in the living room at West Hollywood’s Chateau Marmont. One of her pals brought along a toddler, and Diaz turned on the maternal charm, holding the little boy in her lap, an onlooker says. Still, it was a grown-up night out as the actress sipped red wine and chatted with her friends.

Katy Perry hosted a “Waking Up in Vegas” bash at Haze, a new Sin City nightspot inside Aria Resort and Casino. The singer treated partygoers, including Mickey Rourke, to an impromptu live performance of her hits, and was also joined onstage by Cobra Starship’s Gabe Saporta. But Perry was happy to party, dancing and laughing with her friends into the wee hours of the morning.

• Also in Las Vegas: Lauren Conrad, who celebrated her 24th birthday at the Bank nightclub inside the Bellagio with some girlfriends.