Afterparties, VIP rooms, blue cocktails—celebs did plenty of mingling during Olympus Fashion Week. At a Coty bash, the Olsen twins bumped into Jennifer Lopez, whom they'd never met, and an excited Lopez invited them to her table. Surrounded by bling at the opening of the Sean John flagship, Vivica A. Fox declared, "The energy in the air is just superb." Still, the airborne buzz wasn't enough for everyone. "You have to get lots of candy to keep your energy up," said Lil' Kim at a Baby Phat party, "and make sure your driver is outside at all times." Preferably carrying cash: At the Sean John bash, Naomi Campbell paused at a pile of luxe pillows. "Ooh, these are so soft," she exclaimed. "I'm going to go shopping right now."

Stargazing with Coty

WHERE: Rose Center for Earth and Space at the American Museum of Natural History

WHEN: Sept. 12, 9 p.m. to midnight

WHY: 100th anniversary of Coty

STAR ATTRACTIONS: Coty partners Jennifer Lopez, Mary-Kate and Ashley Olsen, Isabella Rossellini, Kate Moss and Kenneth Cole

GUESTS: Veronica Webb, Bai Ling, Serena and Venus Williams

HIGHLIGHT: Midnight-blue vodka cocktails

Fashion Rocks

WHERE: Radio City Music Hall

WHEN: Sept. 9 from 8 p.m. to 11 p.m.

HOST: Condé Nast Media Group

HEADLINERS: Denis Leary (emcee), Alicia Keys, Beyoncé, Rod Stewart, Avril Lavigne, Usher, Mary J. Blige, Faith Hill, Andre 3000

IN THE AUDIENCE: Jamie-Lynn DiScala, Moby, Tommy Hilfiger, Tony Danza

WORDS TO REMEMBER: "Rock stars dress like beautiful women; my first crush was David Bowie."—Denis Leary

P. Diddy's Do

CELEBRATING: Opening of the Sean John flagship on Fifth Avenue

WHEN: Sept. 9 from 9 p.m. to 11 p.m.

GUESTS: The Black Eyed Peas' Fergie, Zac Posen, Star Jones, Ludacris, Lil' Kim, Naomi Campbell, Paris and Nicky Hilton, Venus and Serena Williams

HIGHLIGHTS: P. Diddy with a trailing entourage of 25; waiters serving Moët & Chandon

HAZARDS: Overzealous bodyguards

OVERHEARD: "I'm from Harlem, 100 blocks away, and for me to be here is amazing. I'm with the big boys now" said the host.