When a pregnant Britney Spears (search) showed up at the "Charlie and the Chocolate Factory" premiere wearing a tank top that read, "I have the Golden Ticket," the Cheetos-lovin' songstress had little idea that she had created one of this year's hottest Halloween costumes (search).

Celeb-mania has reached a new high in this country, with more and more people opting to dress like stars than like crypt keepers. According to a survey by the National Retail Federation (search), actor/famous person is the third most popular costume for adults.

"Everybody is obsessed with celebrities," said Life and Style Weekly Magazine editor Samantha Meiler.

"People all over are wearing the "I have the Golden Ticket" shirt. All they have to do is throw on a Kabbalah string and find somebody to play K-Fed [Spears' hubby, Kevin Federline (search)] and they have a great costume that people will recognize. The worst thing is to have people come up and say, 'What are you?'"

Click here to read about other hot Halloween costumes

Whether you are donning baggy clothes and a Balenciaga bag as Mary-Kate Olsen (search), or wearing short-shorts, a plaid button-down and boots as Jessica Simpson (search)-as-Daisy Duke, Meiler recommends accentuating the trademarks that set your celebrity apart.

"We are having a company 'Dress Like Your Favorite Star' party, and someone is going as Mary-Kate Olsen. She bought a huge tub of popcorn and covered it in Starbucks logos, because Mary-Kate is always walking around with a cup of their coffee."

But boho MK and "Golden Ticket" Britney aren't the only celebs to be on the lookout for.

A sexed-up Paris Hilton (search), mop-topped Donald Trump (search) and poncho-clad Martha Stewart (search) are also hot. So are Tom and Katie.

"I'm going as Katie Holmes (search) and my friend is wearing a bomber jacket and going as Tom Cruise (search), and he's just going to act really obnoxious all night," said 29-year-old Kerry Smith of Brooklyn, N.Y. "I'm brunette, so I'm going to straighten my hair and wear huge sunglasses that cover my face. I'm also going to put a bump under my shirt and say 'Yes' to everything [Tom] says," Smith added.

But as Meiler recommends, the little extras are key.

"I was in Times Square and picked up some Scientology pamphlets. I'm going to walk around with them and hand some out," Smith added.

If L. Ron Hubbard is not your thing, Angelina Jolie (search) is another easy look to pull off: Just pick up a Baby Björn carrier, throw a do-rag on a doll's head, wear a black sweater and top the whole thing off with a pair of aviator sunglasses.

"Anybody can pull off these looks," Meiler said. "A lot of them are pretty simple. All you have to do is grow a little beard, throw on a Red Sox cap and you are Ben Affleck (search)."

While most people are going as a celebrity for the fun of it, some are doing it out of necessity.

"I'm almost 35 weeks pregnant, and there aren't a whole lot of options," said Britney wannabe Sara Cook of Athens, Ga.

"I'm going as Britney, except I'm doing the one where she is walking around with a messy ponytail, smeared makeup and UGG boots."

When asked if she had any defining accessories to accompany her costume, Cook replied:
"I'm going to walk around with a Starbucks cup and a bag of Cheetos."