"La Montagna di Sale (The Salt Mountain)" by Mimmo Paladino is displayed in Piazza Duomo on April 5, 2011 in Milan, Italy.

146 West End Stars hold a flashmob in support of the non-profit organistation Love 146, which campaigns to end child s*x slavery and exploitation, at Trafalgar Sqaure on April 11, 2011 in London, England. (Photo by Tim Whitby/Getty Images)

Afghan police recruits undergo training at the Afghan Police Academy October 5, 2010 in Kabul, Afghanistan. (Photo by Majid Saeedi/Getty Images)

An employee demonstrates a Blackberry Playbook tablet at a Best Buy store on April 19, 2011 in Chicago, Illinois. The tablets, made by Research In Motion, went on sale today in the United States and Canada. (Photo by Scott Olson/Getty Images)

Musician Kirk Hammett of Metallica performs onstage during The Big 4 held at the Empire Polo Club on April 23, 2011 in Indio, California.

Opera singers perform in the pool “AquAria PALAOA” during a rehearsal at the swimming pool Neukoelln on April 27, 2011 in Berlin, Germany. The premiere of the underwater opera AquAria PALAOA is on May 1st. (Photo by Andreas Rentz/Getty Images)

Street fighting in Berlin between Government troops and Spartacists, during the Spartacist uprising which followed Germany's defeat in World War I. (Photo by Keystone/Getty Images). 1919

The Lady Boys of Bangkok have fun at the Meadows August 1, 2006 in Edinburgh, Scotland. (Photo by Jeff J Mitchell/Getty Images)