Although no firm figures are available, a survey by Interactive Week magazine concluded that 10,000 sexually explicit sites could be bringing in as much as $1 billion annually from credit-card charges for accessing the sites. An analyst for one company that tracks use of on-line services reports that more than one in four households owning computers visits such sites monthly.

Sexually explicit sites are among the first to use such advanced (and expensive) technology as T3 phone lines, through which compressed, high-resolution video images can easily be transmitted and viewed. One pornography provider recently announced a $10 million effort offering multiple computer video channels much like cable television.

Says one porn model turned computer entrepreneur (who manages her own Web site featuring herself), "Sex is still the most searched-for word on the Internet, and that's why our service is growing so well." (Source: The Associated Press.)