Marc Malkin

Tana Lee Alves/WireImage.com

Drew Barrymore and T.R. Knight in Sin City, supermodels and moguls in the Hamptons, and here on the West Coast, it was all about Paris Hilton in Malibu. Read on to learn who was doing what this weekend.

Supermodels Karolina Kurkova and Selita Ebanks (above) hosted the launch of Victoria’s Secret’s new Secret Garden body-care collection at the Estate in the Hamptons. Hitting the soiree were Sophia Bush and magician David Blaine.

Also in the Hamptons this weekend were Hollywood moguls David Geffen and Sandy Gallin, who were spotted shopping at Scoop with a muscled, Abercrombie & Fitch-looking young man.

Dan Herrick/ZUMApress.com

Back in New York City, Oscar winner Cuba Gooding Jr. was spotted dancing with a group of friends on Friday night at Bungalow 8.

Who even knew Barrymore and Knight were pals? The two were spotted with a group of friends on Saturday in Las Vegas seeing Cirque du Soleil's Beatles-inspired Love at the Mirage. Later on, they were seen partying at Jet nightclub.

And props to Ms. Barrymore for partying with the people. She opted to dance with regular clubgoers instead of hanging in the VIP area.

Brandy also hit Jet, where she danced atop banquettes during the after-party for the Old School Meets New School Poker Tournament, benefiting the Sports Dream Foundation.

Bare Pool Lounge

Just yesterday, it was a Dancing with the Stars pool party at the Bare Pool Lounge with Kelly Monaco, Regina Poryes, Kym Johnson and Cheryl Burke (above), who were in town for Edyta Sliwinska and Alec Mazo's joint bachelor-bachelorette party. On Saturday, the lovebirds hit up the Bellagio’s Light nightclub, where they danced until the wee hours at a VIP table next to the deejay booth. I’m told they're getting hitched Sept. 1.

Here on the West Coast, I finally made my way out to Malibu to check out the Polaroid Beach House and LG House, the summer event spaces/celebrity hangouts.

2381/Most Wanted/ZUMA Press

The Diesel Barbecue hosted by Svedka vodka at Polaroid became more about what was happening two doors down at Paris Hilton’s summer rental. I counted more than 50 photographers sitting on the shore waiting to snap photos of the hotel heiress, who was hosting a get-together for people like Macy Gray and big-belly-baring Jason Davis.

JC Chasez told us at Polaroid that he had been texting with his fellow 'N Syncer Lance Bass earlier in the day. Bass made his Broadway debut the night before as Corny Collins in Hairspray. “He said he was nervous,” Chasez said.

I also saw Chasez at LG, where he was walking around with a colorful football during a party for Puma Urban Mobility. Also at LG? Tennis champ Jennifer Capriati, Aisha Tyler and blasts from the past Suzanne Somers and Sylvester Stallone.

(I just couldn’t get away from Chasez. I also saw him on Saturday night in L.A. at a joint birthday party for Glamour magazine West Coast editor Blaine Zuckerman and the journo's pal, Fisher Pence.)

Back in Malibu, I stopped by Ralph Lauren’s RRL store, where I spotted former Yahoo! honcho Terry Semel picking up some new items. And just when I thought all rich folk like the Terry Semels of the world pay with an American Express black card, he handed over what looked more like a platinum card.

Donato Sardella/WireImage.com

On Saturday night, Hilton's sister Nicky and her beau David Katzenberg joined a couple more blasts from the past, Raquel Welch and Charlies Angels original Jacyln Smith, at the Natura Bisse skin-care line dinner. Also there were Molly Sims, Stephen Dorff and Pink Taco chief Harry Morton along with his dad, Peter.

Also in Malibu, I hear Fran Drescher filmed a tea party at her home with a slew of friends for a DVD she is producing for her Cancer Schmancer organization. I’m told the DVD, which focuses on cancer prevention and screening, debuts on the Home Shopping Network in October.