LOS ANGELES — Forget who won this year's Oscars, Grammys and Emmys, there are millions of movie, music and TV fans out there just dying to learn which celebrity burps the loudest.

And they'll find out, as well as learn the winners in more than a dozen other categories for film, TV, music, sports, books and video games during tomorrow's 20th annual Kids' Choice Awards.

The event, long the loudest, messiest and at times the grossest of Hollywood's many award shows, has grown into one of the entertainment industry's most popular as well. It's become a hit not only with the 14-and-under set, but with the celebrities who now attend in droves.

"It's just one of those things that's fun to show up at," said Justin Timberlake, the defending burping champion and host of this year's show. "Hey, any awards show you can wear jeans and a T-shirt to is kind of cool."

Jeans and a T-shirt is almost required dress for those honored with an award at this show, as at any moment any of them could be drenched in green, gooey slime, another hallmark of the show. Timberlake himself was sprayed with the stuff in 2001 when he was with his former band 'N Sync.

X Games champion Tony Hawk once skateboarded into a vat of green slime from a platform several stories high. BMX bike champion Mat Hoffman parachuted out of a plane, while on his bicycle, straight into a vat of green goo. Last year, Robin Williams was sprayed with it.

"He seemed to revel in it," says Cyma Zarghami, president of Nickelodeon and MTVN Kids and Family Group, who has been involved in all 20 Kids' Choice Awards. She can recall the show's early days, when it was a struggle just to get a nominee to show up.

"It was a sad day back then, trying to get somebody to accept an award from us," Zarghami recalled with a laugh. "It took a long time to get them to come."

That began to change 10 years ago, and now this year's list of celebrity nominees who are expected to attend includes Will Smith, Halle Berry, Julia Roberts, Queen Latifah and Johnny Depp, who was a sliming victim two years ago. Musical performers include Gwen Stefani and Maroon 5.

The show is done before an audience of 10,000 or so shrieking kids lucky enough to score tickets to it.

"I don't think there's anything quite like walking down the orange carpet with kids screaming the entire time," Zarghami said. "And I think they get it. The minute the celebrities step on the orange carpet, they realize it ain't the Oscars."

As more actors have grown up with the show, it's also become a bigger deal for one of them to take home one of the awards — an orange-colored blimp.

"You grow up watching the Kids' Choice Awards and you never expect to be taking a blimp home," said Drake Bell, the 20-year-old co-star of the teen comedy "Drake & Josh." He claimed his first two last year, for favorite actor and favorite TV show.

It wasn't lost on him, Bell said, that about 25 million votes were cast online for last year's winners.

"It's not like watching the Oscars and it's left to a panel and you go, 'Oh, no, that person shouldn't have won,' " said Bell, who's nominated in the same categories again this year. "If someone is going to go get online, go to www.nick.com and find out how to vote and all that stuff, they're really passionate about it."