Cold Turkey is an interesting tool which makes it easy to prevent your own access to particular websites.
Why bother? If there's work to be done then you may not have the time to visit Facebook, check Twitter or post in your favourite online forums. If you're strong willed and can simply ignore your usual web destinations, then this isn't a problem. If you find yourself sneaking back to particular sites, though, and wasting time you don't really have, then using Cold Turkey to control your online access could be a welcome alternative.
The program is easy to use, providing a built-in list of sites which are checked by default, as well as allowing you to enter custom domains of your own. You can also decide when you'd like the block to end: in a few minutes, an hour or two, tomorrow or next week. And then, just click "Go Cold Turkey" and you'll no longer be able to access these sites: your browser will simply act as if they are down.
At its core, Cold Turkey works by modifying your HOSTS file to block requests for each domain.You can't just edit HOSTS to get back online, though, and there's no "back door" to regain access if need to visit a site urgently, so be very careful in how you use the program.