Google spokesperson Sonya Boralv counters that the company is taking measures to protect the security and privacy of individuals. For one thing, the Search Across Computer feature gives users control over what they upload to the Google servers, allowing people to exclude specific files or types of files. Furthermore, Google Desktop encrypts files before transmitting them to and from Google, and they're stored in encrypted form on Google's servers. In other words, they can't be easily snooped in transit. Finally, Google deletes personal files from its servers as soon as they're downloaded to a user's computer; and if the files aren't downloaded, Google deletes them after 30 days.

However, Bankston points out that, since Google Desktop uploads files whenever they're accessed, frequent users will be continually refreshing Google's servers with the latest copies of their personal files. Google provides a button for clearing all one's personal files stored on its servers, but deleted files may reside there for as long as 30 days, according to Google's Boralv.

To be fair, since Google Desktop is intended for power users, its Search Across Computers feature is not turned on until a user indicates his or her acceptance of the company's privacy policy. "We've tried to take really proactive steps to make sure that people know where their data is going, and how it's going to be handled," says Boralv. "Our role as a service provider is to make it really easy for them to make an informed decision."

Despite these controls, though, privacy advocates are concerned that most people won't understand the implications of uploading their files to a public server. Boralv says that Google has a key to unlock the encrypted files stored on its servers. And, as its privacy policy states, the company will turn over personal information, including users' stored files, to comply with law enforcement requests. And the ongoing controversy over the federal government's secret surveillance of U.S. citizens makes such a possibility more than just theoretical.

"There's a parade of horrible things that could happen" when files are stored on a service provider's servers, says Jonathan Rosenoer, an attorney and author of Cyberlaw. "You'll never know if you're spuriously a target of investigation, and the government has gone fishing through your files."

To its credit, in its privacy policy, Google informs users of its obligations to law enforcement and discloses how the Search Across Computers feature works -- at least it explains it for those who understand it.

"We're not blaming Google for the state of the law," says Bankston. "[But] if they want to 'not be evil,' they should be mobilizing resources towards reforming the law and educating the public about its risks. And, until then, they should be designing around the law," for example, by using peer-to-peer file-sharing technologies instead of storing files on Google's own servers.