GETTY IMAGES/Chad Buchanan
It's a Hollywood tradition for sisters Hilary and Haylie Duff to don costumes and attend AirParty, Hollywood's benefit for the Trevor Project, a 24-hour, free suicide-prevention hotline. This year's red carpet event took place at the Los Angeles Theatre on Oct. 29, 2006.
GETTY IMAGES/John M. Heller
Is that a witch's hat on "CSI: N.Y." star Melina Kanakaredes? Yes, that's what she wore when she received the Ribbon of Dreams Celebrity Hero Award at the 13th Annual Dream Halloween Fundraiser for the Children Affected by AIDS. It was held at the Barker Hangar of the Santa Monica Air Center on Oct. 28, 2006.
AP Photo/Disney
"King of Queens" star Leah Remini, right, poses with her husband, Angelo Pagan, and daughter Sofia at Disneyland's "Halloween Time" in Anaheim, Calif., Oct. 3, 2006. The all-new seasonal event at Disneyland continued through Oct. 31.
GETTY IMAGES/John M. Heller
Jamie Lee Curtis was the host of the 13th Annual Dream Halloween Fundraiser for the Children Affected by AIDS Foundation at the Barker Hangar of the Santa Monica Air Center on Oct. 28, 2006.
GETTY IMAGES/John M. Heller
Child star Dakota Fanning attends the 13th Annual Dream Halloween Fundraiser for the Children Affected by AIDS at the Barker Hangar of the Santa Monica Air Center on Oct. 28, 2006.
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Guess what costume rocker Dave Navarro wore to his Halloween Lingerie And Costume Ball at The Highlands in Hollywood on Oct. 28, 2006.
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Actress Sarah Jessica Parker dressed as herself when she hosted a Halloween Party at the UNICEF House in New York on Oct. 25, 2006. She is a UNICEF ambassador.
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Actor Jerry O'Connell shows off his red, furry costume at the 14th Annual Family Halloween Carnival at Universal Studios Oct. 22, 2006, in Universal City, Calif. The carnival raised money for Camp Ronald McDonald for Good Times, which helps about 240 young cancer patients a year.
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Here's another pirate! Actress Lisa Rinna poses for a picture with her daughters Amelia, left, and Delilah Hamlin at the 14th Annual Family Halloween Carnival, at Universal Studios Oct. 22, 2006. Rinna is married to actor Harry Hamlin.
GETTY IMAGES/Michael Buckner
Actress Minnie Driver arrives at Heidi Klum's 7th Annual Halloween Party at Privilege in Los Angeles on Oct. 31, 2006.
GETTY IMAGES/Michael Buckner
Singer Seal and his wife, model Heidi Klum, arrive at Klum's 7th Annual Halloween Party in Los Angeles on Oct. 31, 2006. (Eve appears to be quite tempted by the apple, presented by the evil serpent.)
GETTY IMAGES/Michael Buckner
Actor Jeremy Piven (could he be Pancho Villa?) arrives at Heidi Klum's 7th Annual Halloween Party in Los Angeles on Oct. 31, 2006.
GETTY IMAGES/Michael Buckner
Paris Hilton is glimpsed at Heidi Klum's 7th Annual Halloween Party in Los Angeles on Oct. 31, 2006.
GETTY IMAGES/Michael Buckner
The piratical Kyle MacLachlan and blue Minnie Driver hang out together at Heidi Klum's 7th Annual Halloween Party at Privilege in Los Angeles on Oct. 31, 2006.
GETTY IMAGES/Evan Agostini
OK, it isn't Hollywood, but there were enough famous people (comedian Margaret Cho, for instance) at Bette Midler's annual Hulaween gala to make it Hollywood East. The event, a benefit for the New York Restoration Project, was held at the Waldorf-Astoria Hotel in New York on Oct. 31, 2006.
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Singer and actress Bette Midler, dressed as Flora the Garden Goddess, arrives at her annual Hulaween gala benefit at the Waldorf-Astoria Hotel in New York on Oct. 31, 2006.
GETTY IMAGES/Evan Agostini
Comedian Joy Behar, dressed as Queen Elizabeth II, and Bette Midler pose together at the Hulaween gala benefit in New York on Oct. 31, 2006.
GETTY IMAGES/Evan Agostini
Martha Stewart, dressed as a black cat, shows her claws at Bette Midler's annual Hulaween gala benefit in New York on Oct. 31, 2006.
GETTY IMAGES/Evan Agostini
Dressed as Flora the Garden Goddess, Bette Midler shows off her head-hose at her annual Hulaween gala, a benefit for the New York Restoration Project, at the Waldorf-Astoria Hotel in New York on Oct. 31, 2006.
GETTY IMAGES/Evan Agostini
Singer Willie Nelson and Bette Midler pose together at her annual Hulaween gala benefit at New York's Waldorf-Astoria Hotel on Oct. 31, 2006. According to organizers, Nelson came dressed as "a grownup." He was the guest of honor at the event.