"SpongeBob SquarePants" is 20 YEARS OLD, and they're having a big celebration at Comic-Con in San Diego this summer.
Nickelodeon also released two really cool posters. One has every character who's EVER appeared on the show on it. And the other one has every celebrity who's done a guest voice over the past 20 years . . . in cartoon form, of course.
It's an impressive list that includes . . . Amy Poehler, Andy Samberg, Betty White, Bob Barker, David Bowie, Dee Snider, Dennis Quaid, Ed Asner, Gene Simmons, Henry Winkler, Ian McShane, Jon Hamm, Kristen Wiig, Mark Hamill . . . Pat "Mr. Miyagi" Morita, Patton Oswalt, R. Lee Ermey, Ray Liotta, Steve Buscemi, Adam West and Burt Ward from the old "Batman" TV show, and Victoria Beckham.
And of course, Ernest Borgnine and Tim Conway as Mermaid Man and Barnacle Boy.