It’s hard to stay focused on the Internet. Pinterest, Facebook, Tumblr; we all have our weak spots. StayFocused lets you pick which sites you waste the most time on and then set limits for yourself. Say you’re addicted to reading Techland. Set a limit of one hour, and after that the site will be blocked for the rest of the day. You can block entire sites, certain subdomains and pages, and even specific types of in-page content like videos and games.
Link: StayFocused