"If you're a US senator and your sex tape is leaked, it could end your career," says Robert Thompson, professor of popular culture at Syracuse University. "If you're Paris Hilton, it makes your career."

Two years ago Red Light District, a little known video company in California, hit the jackpot when it landed distribution rights to the Paris Hilton sex tape, an explicit bedroom video shot by a former boyfriend. The DVD has sold some 600,000 copies, establishing Red Light District as the leading player in a lucrative niche of the pornography industry: a purveyor of explicit videos of famous people, sold to an eager public, often over the vehement objections of the participants.

Paris Hilton