Malin Akerman, Maria Menounos Stun at Chateau Marmont

 John Sciulli

Malin Akerman and Maria Menounos hanging out at Carrera Sunglasses Escape at the Chateau Marmont in West Hollywood.

Countess LuAnn de Lesseps getting her hair styled by Eugene Davidoff at Michael Fredo Salon on NYC's Upper East Side.

— Reality star and PR guru Jonathan Cheban shooting a billboard for Wodka Vodka's new campaign in NYC's Times Square.

Kelly Rowland partying with Destiny's Child group members Beyonce and Michelle Williams at a party for her latest album "Here I Am" for the Moet Rose Lounge in NYC. 

Sophia Bush running the 5k at the San Francisco Marathon to benefit the Nature Conservancy (50% of her customized Water Bobble proceeds went to the cause).

Lisa Gastineau, Maria Menounos, Brittny Gastineau and Patti Stanger chatting at the Gastineau Glamour event in Malibu – the girls sampled the Keratin Complex dry shampoo and VnC cocktails).

Harry Potter's Tom Felton hanging out at Vertigo Sky Lounge at Chicago's Dana Hotel and Spa.

Cameron Diaz and Alex Rodriguez working out side-by-side on the Stairmaster while listening to their iPods at Equinox South Beach.

Karina Smirnoff hanging out with her mom at the launch of Gilt City Atlanta.

Dita Von Teese launching her latest namesake cocktail – the "Cointreau MargaDita" in Dallas. 

Rose Byrne rocking out at W's Symmetry Live concert at W South Beach Hotel & Residences.

AnnaLynne McCord talking to her sister Angel at the Voli Light Vodka sponsored Somaly Mam Foundation event at the SLS Hotel in Beverly Hills.

Jessica Szohr listening on as Jesse Marco played a special birthday shout out from DJ Pauly D for AKR PR's Amanda Ruisi at Avenue in NYC.

Ashley and Mary-Kate Olsen taking sake shots with their friends at Yellowtail in the Bellagio before continuing the party at Gold Boutique Nightclub & Lounge at the Aria Hotel in Vegas.

Entourage star Jerry Ferrara trading in his real cigarettes for two boxes of South Beach Smoke electronic cigarettes in L.A. 

The Office's B.J. Novak celebrating his birthday in the Hollywood Hills, sipping on TY KU Sake with Aziz Ansari and castmate Mindy Kaling.

Cisco Adler putting on an impromptu performance for guests like Kate Voegele, Warren Sapp, Chuck Liddell and his wife Barbara Stoyanoff during the NOHO-hosted X Games Kickoff party at supperclub Los Angeles.

Taryn Manning keeping the party going in the living room of Ciroc Cabana Club until 5 AM after returning from an earlier set at Georgica in the Hamptons.

Michael Shannon taking his wife Kate Arrington and his little daughter Sylvia – who was dressed like Dorothy! – to Film Society of Lincoln Center's screening of The Wizard of Oz.

Amy Smart and Mark McGrath spotted hanging out with David Barton at the DavidBartonGym event at The Roxy in LA on Thursday, July 28.

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