Until now, you couldn't get much bigger than the train on Princess Diana's wedding dress.

How about having your wedding officiated by the pop band Train? Now that's big.

The band's drummer, Scott Underwood, was ordained online by the Universal Life Church -- the same church that ordained Conan O'Brien -- so that he could officiate weddings and vow renewals on stage during the band's California 37 tour.

Train is asking fans to record and submit short videos detailing how they met and their connection to the band. The winners will be married on stage at a Train concert and their families will receive concert tickets so they can attend the weddings. Each ceremony will be followed by a performance of the song "Marry Me."

Underwood is just one of many celebrities who have officiated weddings. Click through the slideshow below to see other famous officiants.

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  • Kathy Griffin

    Brian Anstey and Elka Shapiro are such big Kathy Griffin fans that they asked the "D-List" celebrity to officiate their wedding in 2008. The comedienne just couldn't refuse their request and <a href="http://articles.nydailynews.com/2008-03-09/gossip/17893306_1_elka-shapiro-wedding-nuptials" target="_hplink">told the <em>New York Daily News</em></a> that they were her "kind of people."

  • Conan O'Brien

    The talk show host commemorated his TBS show's anniversary <a href="http://www.huffingtonpost.com/2011/10/28/conan-obrien-gay-wedding-tbs-anniversary-_n_1064193.html" target="_hplink">by marrying one of his staff members to his partner</a> on live television in 2011.

  • Lady Gaga

    Lady Gaga was ordained to marry her friend Tricia Donegan, a New York City yoga instructor, to her partner earlier this year. The singer is also considering officiating weddings at her concerts, <a href="http://www.examiner.com/article/lady-gaga-preps-to-become-ordained-minister-to-perform-pals-same-sex-marriage" target="_hplink">according to Examiner.com.</a>

  • Jason Segel

    Abbe Thorner and Jason Wood were <a href="http://www.eonline.com/news/189118/jason-segel-pronounces-a-couple-husband-and-wife-on-the-tonight-show" target="_hplink">wed by the "How I Met Your Mother" actor on the "Tonight Show with Jay Leno</a>" in July 2010. Their original minister dropped out, but when they saw Segel at a West Hollywood bar, they decided to ask him to preside over their wedding.

  • Tori Spelling

    Tori Spelling married one couple at Chateau La Rue, the bed and breakfast she owns with her husband, Dean McDermott, in July 2007. <a href="http://www.people.com/people/article/0,,20045242,00.html" target="_hplink"><em>People</em> reported</a> that Spelling was "nervous" when she married the pair. "I've done live theater and presented at the Emmys and this by far was my scariest moment simply because they had bestowed such an honor upon me and I didn't want to let them down," she said.

  • Kevin Smith

    Actor Kevin Smith isn't a one-hit-wonder officiant. He'll marry anyone who can pay his $5,000 fee, which includes a venue, Smith's own SModcastle in Hollywood. He officiated one gay couple's hockey-themed nuptials in 2011 and had this to say about the experience: "If you are getting married in hockey jerseys, and you are making me wear a referee jersey, and you are gay ... we are in for a great show," <a href="http://abcnews.go.com/Entertainment/celebrities-kevin-smith-kathy-griffin-tori-spelling-officiate/story?id=13302073#.T_y1YSvLwgU" target="_hplink">Smith told <em>ABC News.</em></a>

  • Fran Drescher

    Drescher officiated a same-sex marriage ceremony in New York on March 6, 2012. The lucky couple won her services through a contest on her Facebook page, and the actress even wrote a <a href="http://www.huffingtonpost.com/fran-drescher/gay-marriage_b_1321853.html" target="_hplink">blog for HuffPost about the experience.</a>

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