Dameon Harris of Nevada gets used to the controls of a bulldozer at Dig This October 27, 2011 in Las Vegas, Nevada. At Dig This, tourists take a short class and can then operate full-size hydraulic excavators and track-type bulldozers in a giant sandbox while being guided by instructors over headsets. (Photo by Ethan Miller/Getty Images)

A poster advertises the highly anticipated video game, “Call Of Duty: Modern Warfare 3” at a GameStop Corp. store November 6, 2011 in North Las Vegas, Nevada. Video game publisher Activision plans to release the eighth installment in the “Call of Duty” franchise at midnight on November 8. (Photo by Ethan Miller/Getty Images)

SI bodypaint model, soccer player Alex Morgan (L) attends SI Swimsuit On Location hosted by Haze Nightclub at the Aria Resort & Casino at CityCenter on February 15, 2012 in Las Vegas, Nevada. (Photo by Michael Loccisano/Getty Images for Sports Illustrated)

Alain Robert, known as the French “Spiderman” climbs the “First” tower, the highest building in France on May 10, 2012 in Paris La Defense, Hauts de Seine, France. (Foto by DPA/AP Photo/Michel Euler)

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)

(L-R) Natalie Burns and Taunia Arave battle as referee Nick Stevens (R) looks on during the US National Sumo Championships at the Riviera Hotel & Casino June 24, 2011 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images)

Singers Steven Tyler (L) and Nicole Scherzinger perform onstage at the iHeartRadio Music Festival held at the MGM Grand Garden Arena on September 24, 2011 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images for Clear Channel)