If you find yourself killing a little too much time on web sites like Facebook, Reddit, and other time sinks, Chrome Nanny can help you keep focused by partially limiting or outright blocking distracting web sites.
Chrome Nanny is similar to Leechblock for Firefox. After installation you can set up white lists, black lists, and the degree to which the black lists are blocked. You can allow yourself 10 minutes per hour of goofing off on Facebook time for example, block it during work hours, or block it all the time. Chrome Nanny can always be disabled or uninstalled if you’re desperate for your Facebook fix but for a gentle reminder to get back to work and stay focused it’s quite effective.
Chrome Nanny [Google Chrome Extensions]