On the website Silk Road, a sort of eBay for drugs hidden in a dark corner of the web known as Tor, Bitcoins are the only means of transaction.

ECONOMIST: Bitcoin

Russian hackers, meanwhile, took to the Net, launching waves of distributed denial-of-service attacks against the country's government, banking and media Web sites, using thousands of personal computers hijacked with hidden software to overload the servers.

FORBES: Worst Cybersecurity Meltdowns

The Oregon has modes for hiking, driving and geocaching, the game of finding hidden objects using only GPS locations posted on Web sites.

FORBES: The compleat option for the compleat wayfarer.

Countries are ranked on "perception" of corruption because statistical collection of illegal activities "are deliberately hidden and only come to light through scandals, investigations and prosecutions, " the Transparency Index web site says.

CNN: Best, worst nations for corruption

Hidden at the bottom of the search options, where you might not spot it at first, is "web search".

BBC: Facebook��s Graph targets Google