eldavojohn writes "In my browser, I regularly go to the tools menu and clear my private data. This includes my cookies. As a result, people like me who destroy cookies by the thousands may be inflating estimates of Web traffic by up to 150 percent. People have good reasons for clearing out cookies — we've heard about bad cookies before (and I think the FCC is still investigating the issue). But every time you delete cookies, many of the sites you've visited count you as a new visitor next time."