Spew by Neal Stephenson
This story was written by Neal Stephenson, and was first published in Wired in 1994. The story is presented in the form of a letter from the main character, Stark, to a female cyberpunk whom he meets in the course of his work. In the story, most information and media channels are hooked together in something called the Spew. This is a version of today's Internet, except it congregates all sorts of information (from credit card transactions, to security camera feeds). It is possible to profile people in a most complete way because the Spew was allowed by the government to be insecure. Stark is hired as a Profile Auditor, someone who tracks other people and their profiles in the Spew in order to track consumer trends. He does this inside the Demosphere, or in DemoTainment Space, which is a virtual reality representation of the Spew. He comes across a woman whose profile seems "too normal" and discovers that she is a cyberpunk, using the Spew to her own advantage without being tracked.
Source: http://www.wired.com/1994/10/spew/
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