Here’s your chance to easily opt out of many of those ad-trackers that follow your every move as you surf the Internet. A new, free tool called TACO, or Targeted Advertising Cookie Opt-Out, lets you do just that.

Developed by a student fellow at the Berkman Center for Internet & Society, TACO places cookies in your browser that prevent 84 online ad networks from tracking your browsing habits. Right now, the tool works only with the Firefox browser.

Without TACO, you’d have to visit a large number of Web sites individually and opt out of each network’s program. —Donna Tapellini