British forces clash with colonial militia during the Battle of Bunker Hill in 1775, as depicted in an illustration. Hulton Archive/Getty Images hide caption

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If Greta Garbo — the iconic movie star who famously wanted to be left alone — were around today, she might be a prime customer of the online privacy industry. Fox Photos/Getty Images hide caption

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Actress Reese Witherspoon is among a number of celebrities who yearn for privacy. Peter Kramer/AP hide caption

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A demonstrator waves a flag marked with the peace symbol on Jan. 26, 1991, during an anti-Gulf War rally at the U.S. Capitol in Washington, D.C. Kevin Larkin/AFP/Getty Images hide caption

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President Obama has "often confounded his opponents by defying political stereotypes," says Julian Zelizer, a presidential historian at Princeton University. Saul Loeb/AFP/Getty Images hide caption

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The USS Barry launches a Tomahawk cruise missile Saturday in support of Operation Odyssey Dawn. The operation targeted radar and anti-aircraft sites along Libya's Mediterranean coast. U.S. Navy/Getty Images hide caption

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A fallout shelter sign graces the Madison County Courthouse in Huntsville, Ala., in 2007. The county is working on a plan to identify shelters that can house up to 300,000 people in the event of a nuclear incident. Dave Martin/AP hide caption

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A 1923 earthquake leveled much of Tokyo and Yokohama, Japan, killing more than 140,000 people. AP hide caption

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A True Hero? President Obama presents the Medal of Honor to Staff Sgt. Salvatore Giunta in the East Room of the White House last November. Asked if he's a hero, Giunta said, "I am only mediocre. I'm average, and by no means did I do anything that anyone else wouldn't have done in that situation." Courtesy of the White House hide caption

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A VU Pioneer TX-9500 II. There are still people willing to drop a large chunk of their income on the best audio equipment available, says music professor Mark Katz. "That said," he adds, "the landscape — or perhaps soundscape — has changed." dogulove /via Flickr hide caption

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