You (hopefully) already know the king of web retail is mining data based on your shopping habits, location, music taste, and other fairly obvious lifestyle indicators.

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Monster jobs web site has one, 6sense that is a data mining search engine that scans your resume and tracks it through the company, but you have to get past 6sense first.

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Usama came to the U.S. to earn his PhD in data mining, now perhaps the most coveted expertise for anyone in the web business.

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So does DoubleClick, a data-mining ad "network" that monitors behavior on 1, 400 Web sites and has more than 80 million user profiles in its database.

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