The Web's New Gold Mine: Your Secrets

Data miners are striking gold with new software, tracking your moves in real time- where you go, what you do, what you prefer- basically a complete profile of your internet habits. The internet used to be a lonely place, but now you are never alone.

Tracking technology is getting smarter and more intrusive. Monitoring used to be limited mainly to "cookie" files that record websites people visit. But the Journal found new tools that scan in real time what people are doing on a Web page, then instantly assess location, income, shopping interests and even medical conditions. Some tools surreptitiously re-spawn themselves even after users try to delete them.