every year, chris hoofnagle organizes the us big brother awards under the auspices of a public interest group called privacy international. "these are awards we give out to government institutions and businesses who've done the most to invade our privacy," says hoofnagle, who also serves as deputy counsel for the electronic privacy information center (epic), another public-interest group concerned with maintaining civil rights on the internet.

the awards won't be announced until march, but hoofnagle recently received a nomination that he found particularly worthy of investigation. representatives of a web site called google watch sent him an e-mail complaining about privacy infringements by none other than the web's most popular search engine. basically, the e-mail accused google of disseminating spyware. google, the message said, was using its toolbar application to collect reams of information about the surfing habits of the world's pc users.

to most users, the google toolbar, available for download at google.com, is simply a convenient means of searching the web. when you install the app on your pc, it integrates with your web browser, giving you an unobtrusive command bar with a text-entry box you can use to quickly and easily send a query to google's online search engine. you type a query into the box, and your browser, jumping to google.com, immediately displays the results.

google collects a good deal of information about your query. it records not only what you searched for (when you activate the advanced toolbar features), but several other pieces of information as well, including the time of day, the type of browser you're running, the language your browser uses, and your ip address. many times, after giving you a list of web sites that match your search, google will also record which sites you actually visited. "google may choose to exhibit its search results in the form of a 'url redirecter,'" reads google's main privacy policy. "when google uses a url redirecter, if you click on a url from a search result, information about the click is sent to google."

of course, the company collects all this information if you enter a query directly into google.com without using the toolbar. the problem with the toolbar is that, if the app's advanced features are running, google also keeps a record of every single site you visitwhether you're using the app to search the web or not.

one of the advanced toolbar features is a service called pagerank. with this activated, when you visit a web site, a small pagerank icon in the toolbar gives you a rough indication of how popular the site is. if the site is particularly popular, you'll see a long green line. if not, you'll see a short green line. when this service is turned on, google keeps a complete record of every web site you visit. "if you choose to enable the google toolbar's advanced features (e.g., viewing the pagerank of web pages)," says the toolbar privacy policy, "the urls of the sites you visit will automatically be forwarded to google." the only way google can provide the pagerank service is by collecting this information.

the presence of software that collects information about users' online behavior has become extremely common on the world's online pcs. webroot, makers of an application called spy sweeper that helps users remove spyware from their systems, says that there are over 6,000 forms of spyware loose on the internet today. this includes not only cookies and browser aids like the google toolbar, but also adware that tracks your behavior to target you for pop-up advertisements; keystroke loggers and other system monitors that let others lift extremely personal information like e-mail from your system; and trojan horses that give hackers complete access to your pc, letting them not only track your behavior but also control your system, changing settings and deleting files. according to research firm gartner, adware alone has found its way into over 20 million pcs across the world.

what makes google practices particularly worrisome is that its services are used by such a wide audience. the company collects 150 million queries a day from more than 100 different countries. but on the upside, because google has such a high profile, the company is under pressure to inform internet users about its practices. before you install the google toolbar, the company explicitly warns you that, in using pagerank, "you may be sending information about the sites you visit to google" and gives you the opportunity to disable the service. the toolbar privacy policy explains how to disable pagerank after you've installed the app. and, through both the main google privacy policy and the toolbar privacy policy, the company gives a complete description of the information it collects and how it uses that information.

generally, when the company records your surfing habits, it does not link this data to your name or any other "personally identifiable" information. "google does not collect any unique information about you (such as your name, email address, etc.) except when you specifically and knowingly provide such information," reads the main privacy policy. and when it does collect this sort of information, the company does not rent or sell it to other businesses or organizations.

"google strives to uphold the highest level of integrity and respect for our users' information," says google vice president of corporate development, david drummond. "google does not share non-aggregate user information with third parties and we treat the integrity and security of user information seriously."

the company does, however, share records of users' surfing habits with people outside the company: "google may share information about you with advertisers, business partners, sponsors, and other third parties." and, as is the case with any business, the company "will release specific personal information about you if required to do so in order to comply with any valid legal process such as a search warrant, subpoena, statute, or court order."

should you be worried about information google is collecting? chris hoofnagle is. "i thought [the google toolbar] was something that let you use the web more easily, not something that let the company track you," he says. "i'm rather astounded."