Computer databases already have a lot on us: Credit cards keep track of airline ticket purchases and car rentals. Supermarket discount programs know our eating habits. Libraries track books checked out. Schools record our grades and enrollment.

On top of that, government agencies generate amass information on large cash transfers, our taxes and employment, even driving history.

What if computers become smart enough to link all those government and commercial resources and discern patterns from people's electronic traces? New technologies are meant to make us feel safer and more secure. But they also stir concerns that we are unwittingly building a surveillance society.

[ Read more ]