Fifty years ago, in 1984, George Orwell imagined a future in which privacy was demolished by a totalitarian state that used spies, video surveillance, historical revisionism, and control over the media to maintain its power. Those who worry about personal privacy and identity--especially in this day of technologies that encroach upon these rights--still use Orwell's "Big Brother" language to discuss privacy issues. But the reality is that the age of a monolithic Big Brother is over. And yet the threats are perhaps even more likely to destroy the rights we've assumed were ours. Database...