hmmm...I can take an educated guess at who visited my site by looking at the stats, which include name of ISP, browser,OS, screen resolution, length of visit, pages viewed, referring link, and IP # if they have visited before. (If Joe tells me he looked on Tuesday and he doesn't clear his cookies, then looks on Thursday, I see him as a repeat visitor with entries for both days.) Broadband has given many of us IP addys that don't change often. If I wanted to visit a site discreetly, I would use a library computer, a dial up connection, or a proxy host.
Before anyone gets hopping mad that their computer is reporting all this info to the webmasters, stop and think: If a webmaster knows how people are using the site, he can make the site suit their needs better, and in business, that is critically important. (Imagine if NewEgg had a hard to use site? shudder) Plus, your browser has to communicate what it has to work with to the server which needs to know what info to release, and in what format.