A screen shows the new Automated Target Recognition software as a TSA employee, who couldn't provide her name, waits to walk into the advanced imaging technology unit to demostrate the new software that has been installed at Miami International Airport on August 23, 2011 in Miami, Florida. The new software is designed to enhance passenger privacy by eliminating passenger-specific images and instead auto-detecting potential threat items and indicating their location on a screen which shows a generic outline of a person. (Photo by Joe Raedle/Getty Images)

Patrick Boyle, The Earl of Glasgow and his son David, Viscount Kelburn pose at their home Kelburn Castle on August 30, 2011 in Largs, Scotland. The Earl of Glasgow has asked Historic Scotland if the graffiti can remain as a permanent feature of the Castle. The local council allowed the mural to be painted on the wall by Brazilian artists in 2007, with a three year limit put on the graffiti pending the start of rendering work at the castle.(Photo by Jeff J Mitchell/Getty Images)

NASA space shuttle Atlantis in Earth orbit is seen during a Rendezvous Pitch Maneuver, or back flip to enable space station crew members to take high resolution digital pictures of the shuttle's heat shield before docking for the last time with the International Space Station July 10, 2011 in space. Atlantis has embarked on a 12-day mission to the International Space Station where it will deliver the Raffaello multi-purpose logistics module packed with supplies and spare parts. This will be the final launch of the space shuttle program, which began on April 12, 1981 with the launch of Colombia. (Photo by NASA via Getty Images)

An arial view of Top Pearsy's Maize Maze in the shape of Harry Potter, on July 11, 2011 in York, England. Farmer Tom Pearcy has cut two portraits of Harry Potter in his crop of maize plants. With some subtle differences the two images create the world's largest spot the difference competition. At over 50m in diameter, and cut out of over 1 million living maize plants, the York Maze is the largest “Maize Maze” in Europe and one of the largest in the world. (Photo by Bethany Clarke/Getty Images)