A man uses a computer during the 25th Chaos Communication Congress in Berlin
A man uses a computer during the 25th Chaos Communication Congress (25C3) in Berlin, December 27, 2010. The annual four-day conference, organized by the Chaos Computer Club (CCC), offers lectures and workshops and attracts an international audience of hackers, scientists, artists, and utopians. The 25C3s slogan is "Nothing to hide", the organiser's website said. REUTERS/Thomas Peter (GERMANY - Tags: SCI TECH SOCIETY)