Bugs can, however, be written to reach across the Internet into unprotected computers and steal files. It protects by routing data through the Montreal-based company's network servers, which strip off identifying information about users before sending the data to a Web site. By masking the numerical Internet address that identifies a user's computer, Web sites are prevented from tracking the user, who effectively surfs under an alias. Dozens of other privacy protection products exist, including Privada, Anonymizer, IDzap and Somebody. About a half dozen privacy products block banner ads and some are effective against Web bugs, says Richard Smith, chief technologist of the Denver-based Privacy Foundation.
Web bugs can be fairly innocuous, providing advertisers with data on who is visiting a Web site.
Or they can be intrusive, passing information that surfers enter into online registration forms to advertisers or marketers, said Smith. Web bugs need cookies to function. So it's sort of putting social pressure on Web sites. Intelytics is working on a product called Personal Sentinel that Wang said would work similarly. Programs including Webwasher, IDcide and AdSubtract block out banner ads, cookies and some Web bugs, said Smith.