A Washington man talking on his cellphone may be taking a health risk, according to an analysis from the World Health Organization that finds a possible risk of cancer from exposure to the devices. Nicholas Kamm/AFP/Getty Images hide caption

itoggle caption Nicholas Kamm/AFP/Getty Images

A student works on her robot gladiator. Courtesy of National Tooling and Machining Association hide caption

itoggle caption Courtesy of National Tooling and Machining Association

David Jackson (left) and Dave Petrillo of Coffee Joulies brought in more than $300,000 using Kickstarter.com. Paul Agus/Courtesy of Coffee Joulies hide caption

itoggle caption Paul Agus/Courtesy of Coffee Joulies

A portrait of David Quiring Sr. This is the first image that appears when you scan the QR code at his grave. See his QR website. Courtesy of Quiring Monuments hide caption

itoggle caption Courtesy of Quiring Monuments

President Obama, with Facebook CEO Mark Zuckerberg, speaks during a town hall meeting April 20 at Facebook headquarters in Palo Alto, Calif. Mandel Ngan/AFP/Getty Images hide caption

itoggle caption Mandel Ngan/AFP/Getty Images

LinkedIn CEO Jeff Weiner, center right with beard, and Reid Hoffman, center background with glasses, listen to traders during their company's listing on May 19 on the New York Stock Exchange. The company reached a market value of $9 billion last week, leading to fears of another dot-com bubble. Mark Lennihan/AP hide caption

itoggle caption Mark Lennihan/AP

A recent view of Earth from the International Space Station. NASA hide caption

itoggle caption NASA