By ET Online Staff
3:00 AM PDT, July 17, 2011
Lady Gagaflashed a…lady product when going pants-less for an opening performance for the Pussycat Dolls in 2009.
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Lady Gaga

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Lady Gaga flashed a…lady product when going pants-less for an opening performance for the Pussycat Dolls in 2009.
Jennifer Lopez

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At the 2009 American Music Awards, actress/singer Jennifer Lopez took a nationally televised tumble. During the boxing-themed routine to her single "Louboutins," Lopez climbed on the backs of her dancers and jumped off only to fall on her famously well-endowed tush. She immediately got back up with her game face on and played it off like a champion.
Britney Spears

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During the final leg of her 'Circus' tour, Britney forgot what city she was in. Forty minutes into her performance in San Jose, California, she yelled, "What's up, Sacramento?" Yikes!
Beyonce

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Beyonce Knowles fell down an entire flight of stairs while performing in Orlando, Florida. Despite rolling down center stage and landing flat on her face, Knowles continued the song and the remainder of the show like a professional as though nothing had happened. She later kindly told fans, "If you taped this, please don't put it on YouTube!"
Steven Tyler

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"American Idol" judge and Aerosmith front man Steven Tyler fell backwards off the stage during a performance in Rapid City, South Dakota last year. The lead singer was airlifted to a hospital, where he received treatments or a shoulder injury and minor head and neck injuries.
Jessica Simpson

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Ashlee's older sister, Jessica Simpson, forgot the lyrics during a Dolly Parton tribute in 2006, alongside legendary musician Kenny Rogers. The following year, she made her band start over on live television for an appearance on "Good Morning America," where she forgot the introduction to her own song, "With You."
Ashlee Simpson

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In 2007, singer Ashlee Simpson was caught lip-syncing on an episode of "Saturday Night Live" due to technical difficulties. Simpson, feeling embarrassed, exited the stage doing a nervous jig and later blamed an injured voice and gastric distress for the necessary backup music.
Janet Jackson

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Janet Jackson experienced a nationally televised "wardrobe malfunction" during the conclusion of her Super Bowl halftime performance alongside Justin Timberlake in 2004. Timberlake pulled on the breast of Jackson's top, revealing a silver sequined pasty.
Fergie

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Fergie admitted to wetting her pants during a 2005 performance with the Black Eyed Peas in San Diego, California. In response to the incident, Fergie claimed she had had a few drinks prior to the show and did not think to go to the bathroom ahead of time. She later explained the incident to Scotland's Daily Record, telling the newspaper: "we were jumping around -- it was all very rock and roll-- and my bladder just started to... you know."
Christina Aguilera

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Christina Aguilera faced an onslaught of criticism after forgetting the lyrics to the National Anthem during the nationally televised Super Bowl in Dallas, Texas. In an attempt to then redeem herself at the 53rd Annual Grammy Awards, the singer not only fudged lyrics during an Aretha Franklin tribute, she also tripped onto her knees.
Yikes! The Most Embarrassing Celebrity On-Stage Moments

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Everyone is entitled to an "oops" every once in a while, but when you're a celebrity even one mistake can land you some serious, long-lasting public humiliation.
Join us as we count down some of the very most embarrassing on-stage celebrity moments in recent history.