Ke$ha performs live on stage during the second day of the Wireless Festival at Hyde Park on July 2, 2011 in London, England. (Photo by Jim Dyson/Getty Images)

Singer Rihanna performs onstage during the 2011 Billboard Music Awards at the MGM Grand Garden Arena May 22, 2011 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images for ABC)

Actors Justin Timberlake (L) and Mila Kunis present an award onstage during the 2011 MTV Movie Awards at Universal Studios' Gibson Amphitheatre on June 5, 2011 in Universal City, California. (Photo by Kevin Winter/Getty Images)

A fan lies passed out on the first day of the Wacken Open Air heavy metal music fest on August 4, 2011 in Wacken, Germany. Approximately 75,000 heavy metal fans from all over the world have descended on the north German village of 1,800 residents for the annual three-day fest. (Photo by Sean Gallup/Getty Images)

A model presents a creation during the Biofashion show, which features designs made from plants, recycled and natural materials, in Cali, Colombia, November 19, 2016. BioFashion is an environmental initiative that seeks to create awareness about the preservation and management of natural resources where new designers develop dresses made with living plants, flowers and organic elements. (Photo by Jaime Saldarriaga/Reuters)

Participants run through the flames in the 2011 Spartacus Challenge on October 2, 2011 in Wolverhamton, England. (Photo by Dean Mouhtaropoulos/Getty Images)

Miss World 2011 participants Miss USA, Miss Canada, Miss Mexico, Miss Guatamala, Miss Costa Rica, Miss Dominican Republic pose beside the Thames during a photocall as part of the Miss World 2011 UK Tour, on October 31, 2011 in London, United Kingdom. The tour celebrates Miss World's 60th birthday. The final of the competition will take place in Earls Court, London on Sunday 6th of November. (Photo by Ian Jones /Miss World Ltd via Getty Images)

Sorana Cirstea of Romania hits the ball against Jie Zheng if China during the Sony Ericsson Open at Crandon Park Tennis Center on March 22, 2011 in Key Biscayne, Florida.