Search Vs. Security

Google Inc.'s Desktop Search software doesn't come with a warning label, but perhaps it should. Google recently introduced an application that lets users search a hard drive for E-mail files, Web-browsing history, and other local documents using Google's Web interface. It's a photographic memory for your computer, Google says. Desktop Search indexes and stores versions of files and other computer activity in order to make the information easier to find.

The biggest risk comes when the app is used on a computer not under the control of a single user, such as when someone uses a public computer to check E-mail or download a file. Subsequent users of that computer might be able to look at those E-mails or access a copy of the file. "This isn't a great application for cybercafes or library terminals," says Marissa Mayer, director of consumer Web products at Google.

The application presents a challenge to those who rely on security through obscurity. "It's a double-edged sword," says Richard Smith, an Internet privacy and security consultant. "It's great for organizing. The downside is it's also a spying tool."

"We can only make Desktop Search as secure as your computer," Mayer says. "Generally, we think this application should be used on a computer that you use as a single user over time, where you really do build up a history." When multiple people share a computer, she recommends using separate accounts with passwords.