Just discovered an extension for Google Chrome called "Chrome Nanny" (https://chrome.google.com/extensions...anphofpplhmcmn) recently - you can set it to block any websites you feel you visit too much, or you can allow yourself to visit them for, say, 15 minutes a day. I've found that I can get very distracted by online newspapers and Facebook, so I've blocked those until after my exams. There's also a "lockdown" mode which will block any website(s) for a specified length of time - that can't be undone once you've set it up, so might be useful if you're worried you might unblock the websites.

There's an equivalent for Firefox called "Leechblock". (https://addons.mozilla.org/en-us/fir...on/leechblock/)

Just thought that might be of use to someone, only found out about it recently so apologies if it's already been posted.