LONDON, ENGLAND - MARCH 23: An employee holds Banksy's 'Girl and Balloon' which was painted on an Ikea frame at Bonhams auctioneers on March 23, 2012 in London, England. The painting, estimated at GBP 15,000 - 25,000, USD 24,000 - 40,000 and 18,000 - 29,000 euros, forms part of the Urban Art Sale, which takes place at Bonhams on March 29, 2012. (Photo by Peter Macdiarmid/Getty Images)