Arthur Miller

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Playwright Arthur Miller said his desire to be religious "just vanished." One of his most famous plays, "The Crucible," can be read as an attack on the unquestioned power of organized religion.

Bill Gates

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Microsoft chairman Bill Gates has indicated agnosticism when he said he doesn't know if there is a god, but he added, "I think religious principles are quite valid."

Adam Carolla

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"Loveline" host Adam Carolla often talks about his atheism.

Brad Pitt

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In recent interviews, Brad Pitt has called himself "probably 20 percent atheist and 80 percent agnostic." Which places him 100 percent in this slideshow.

Christopher Hitchens

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Fiery writer Christopher Hitchens landed at the top of the NYT bestsellers list with his excoriating 2007 screed "God Is Not Great."

Daniel Radcliffe

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The "Harry Potter" franchise has already garnered the ire of some Christian groups, and recently star Daniel Radcliffe told Telegraph that he is an atheist, but is "very relaxed about it."

Ernest Hemmingway

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Though there is reason to dispute his actual status as an atheist or agnostic, his novel "For Whom the Bell Tolls" includes a line often cited by atheists: "All thinking men are atheists."

George Clooney

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George Clooney, in an interview with Larry King, circumvented giving a direct answer to the question of religion, but ultimately admitted, "I don't happen to have those beliefs as much."

Guy Pearce

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In an interview with the L.A. Times, actor Guy Pearce said he doesn't believe in god and also said he enjoys wearing a shirt that reads: "Jesu$ Saves."

Jack Nicholson

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Jack Nicholson espoused his lack of belief in God in an interview with Vanity Fair in the early 1990s.

Joaquin Phoenix

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Joaquin Phoenix said he doesn't believe in god, an afterlife, or the concept of souls. "To me it's a pretty preposterous idea."

Julia Sweeney

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Former "Saturday Night Live" cast member Julia Sweeney wrote a book about her experience as an atheist called "Letting Go of God."

Julianne Moore

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Julianne Moore, like a few actors answering "Inside the Actors Studio" host James Lipton's question about what they'd say to God when they arrive at Heaven's gate, quipped, "I was wrong, you do exist!" At one point, Lipton used the line himself.

Lance Armstrong

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In a Time Magazine interview, Lance Armstrong said: "I don't have anything against organized religion per se. We all need something in our lives. I personally just have not accepted that belief. But I'm one of the few." He also said if there was a god, he would still have both of his testicles.

Larry King

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Larry King was asked by Barbara Walters if he believed in God and his answer was, simply, "No."

Luis Bunuel

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Legendary director and satirist Luis Bunuel seemed to make his career out of offending the church. His Palme d'Or winner "Viridiana" mocked the Last Supper, and he was quoted as saying, tongue planted in cheek, "Thank God I'm an atheist."

Mark Zuckerberg

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Facebook founder Mark Zuckerberg listed, on his Facebook profile, "Atheist" under "Religious Beliefs."

Omar Sharif

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Oscar-nominated actor Omar Sharif has, in his life, moved from Catholicism to Islam to atheism.

Richard Dawkins

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Daniel Radcliffe said he also respects people like author Richard Dawkins, who are more outspoken about their atheism. An evolutionary biologist, he has written sharp criticism of the theories of creationism and intelligent design.

Salman Rushdie

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Salman Rushdie landed in hot water when his "The Satanic Verses" was published. A fatwa was even called on him by Ayatollah Khomeini. A recent interview has revealed him as an atheist.

Sarah Silverman

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Sarah Silverman has said she is only Jewish culturally speaking. She said, "I have no religion."

Seth MacFarlane

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Seth, the creator of Family Guy, has confirmed that he is an atheist during a Bill Maher interview.