Meet the cataphiles: Daniel Garnier-Moiroux crawls through a very tight section of the Paris catacombs. Stephen Alvarez/National Geographic hide caption

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Las Vegas police stand guard outside Harrah's hotel-casino in Las Vegas on Feb. 21, 2006. As officer Norman Jahn recalls, police arrested the suspected gunman without firing a shot. Jae C. Hong/AP hide caption

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Andrei Grigoryev, 43, is a federal game warden, or forest ranger. After he chased after a hunting party last winter, he ended up being charged with abuse of power. He now faces four to 10 years in a Russian jail. Grigoryev fears he is falling victim to a Russian federal court system that convicts almost everyone. Boris Ryzhak/NPR hide caption

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A woman pushes her luggage past an array of flowers laid out a day after the deadly explosion at Domodedovo Airport near Moscow as people wait in line for a security check. Sergey Ponomarev/AP hide caption

itoggle caption Sergey Ponomarev/AP

Economist Paul Krugman says the European economic crisis has "all the aspects of a classical Greek tragedy." iStockphoto.com hide caption

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