Earlier this week, Blink182 drummer Travis Barker announced that he wouldn't be joining his band for a concert in Australia because he was too afraid to fly Down Under. (With good reason -- Barker was involved in a horrifying 2008 plane crash in South Carolina that claimed the lives of four people, two of whom were his best friends.

But Barker is hardly the only celebrity to experience fear at seemingly everyday things. From David Beckham to Oprah Winfrey, Hollywood hotshots have copped to having pretty unusual phobias. Flip through the gallery below to learn more about what scares the bejeezus out of these stars.

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  • David Beckham

    The famous footballer admitted that his obsessive compulsive disorder was "tiring" and that he feared disorder. "I've got this obsessive compulsive disorder where I have to have everything in a straight line or everything has to be in pairs. I'll put my Pepsi cans in the fridge and if there's one too many then I'll put it in another cupboard somewhere," he told Esquire magazine.

  • Aretha Franklin

    The "Natural Woman" singer hasn't flown in over 30 years and travels only by bus and car for her performances. "The last time I flew was in '82. I had such a bad flight. A two-engine plane. The flight was dipsy-doodlng up and down all the way home. I said, 'Oh my God, when I get to Detroit, that's it. That is it.' And I have not flown since," <a href="http://www.time.com/time/magazine/article/0,9171,1966458,00.html">she told Time magazine </a>in 2010.

  • Johnny Depp

    Maybe he just read too much Stephen King: Johnny Depp was once scared witless of clowns. "Something about the painted face, the fake smile. There always seemed to be a darkness lurking just under the surface, a potential for real evil," <a href="http://www.sfgate.com/style/article/JOHNNY-DEPP-3058155.php">he has said about his phobia.</a>

  • Kristen Stewart

    The actress had to overcome her fear of horseback riding for her role in "Snow White and the Huntsman." "I got to jump off cliffs and ride horses, and that terrifies me," <a href="http://www.peoplepets.com/people/pets/article/0,,20579708,00.html">Stewart revealed</a>. "I was really, really not happy about having to do all that [horseback riding]. I don't like that -- I hate that."

  • Billy Bob Thornton

    Angelina Jolie's ex-husband is famously grossed out by antique furniture -- yes, old furniture. "It's that French/English/Scottish old mildewy stuff," <a href="http://www.nytimes.com/2012/05/17/garden/billy-bob-thornton-on-his-new-memoir-the-billy-bob-tapes.html?_r=0">Thornton explained to the New York Times</a> in 2012. "Old dusty heavy drapes and big tables with lions' heads carved on it. Stuff that kings were around. That's the stuff I can't be around. It was too big to be functional. It creeps me out."

  • Pamela Anderson

    Say what? The former "Baywatch" babe reportedly has eisoptrophobia, or a fear of mirrors.

  • Nicole Kidman

    This native Australian beauty apparently didn't like to play in the bush all that much: She's afraid of butterflies. She told In Style magazine: "It's so bizarre. I'm not afraid of snakes or spiders. But I'm scared of butterflies."

  • Oprah Winfrey

    Talkative as she may be, you'll never hear Oprah snapping her gum. "Do you know I have a whole thing about gum? In Mississippi, my grandmother used to chew gum, then stick it in the cabinet. There were rows and rows of Juicy Fruit and Spearmint. I was afraid of it. Even now I don't allow gum in the building where I work," <a href="http://www.oprah.com/omagazine/Oprahs-Interview-with-Jamie-Foxx/2#ixzz2LgcLglr0">she told Jamie Foxx in an interview with the star in O Magazine.</a>

  • Keanu Reeves

    Was it all that time spent in the "Matrix"? "I am afraid of the dark. But I mean that in a real philosophical way," Reeves is reported to have said.

  • Jennifer Love Hewitt

    She'll take the stairs, thanks: The "Client List" actress reportedly is terrified of riding in elevators.

  • Jennifer Aniston

    After a bad experience of flying through an electrical field, Aniston became terrified of traveling up in the air. "What scares me is taking off, because I don't understand how the plane gets up there. I've heard all about the aerodynamics, the speed, the engine. Of course, when your number's up, it's up. Maybe I'm just a control freak. I'm still nervous -- though much better than I was," <a href="http://www.chinadaily.com.cn/entertainment/2006-05/30/content_604269.htm">she has confessed</a>.

  • Matthew McConaughey

    Would it help if he just took his shirt off? McConaughey just can't seem to get the hang of revolving doors and tunnels. "I don't like revolving doors, and I really don't like that blindspot when you're driving and go into a tunnel. You know that spot where you can't see for about 10 feet. You can't see what's in front of you or if someone's broken down or something in front of you,"<a href="http://www.starpulse.com/news/Noelle_Talmon/2008/12/03/matthew_mcconaughey_discusses_surfer_dud"> he has said</a>.

  • Christina Ricci

    “They are dirty! If I have to touch one, then it freaks me out,” Christina Riccia reportedly said about her fear of, of all things, house plants. "Honestly, I can’t go near them.”

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