You may not recall all the searches you've done -- but Google Dashboard will help you remember. As the Globe reports, that's because every search you perform is recorded and preserved for future analysis, "to help Google improve its service." The Globe reporter was able to review his Web searches going back to 2006 -- including inquires for "airline tickets, books and magazine articles, [and] a new clarinet for my daughter."

If you sign up for other Google services, you give the company access to all sorts of other information you might have thought was private. Google offers free e-mail, an online appointment calendar and address book, document creation and management, and the Google Voice telephone and messaging service. Each encourages you to supply specific information about you, your friends, family and business colleagues.

If someone hacks into Google's system and grabs the data -- or if a hacker simply guesses your Google password -- there's no limit to the profit opportunities such a privacy invader might seize at your expense

So what can you do to protect your privacy? At the extreme, you could stop using the Internet. Or you can be selective about which Web sites you give your personal information to. Keep your address book private, remove cookies from your browser, and use an ad blocking program.

If evil people were running Google, there's no telling what they could do -- it might make a compelling horror movie. But if you produce that film, make sure you don't buy anything through a Google search that could give hackers access to your credit card details.

Peter Cohan is a management consultant, Babson professor and author of nine books, including Capital Rising (due in June 2010). Follow him on Twitter. He has no financial interest in Google securities.