There’s a nifty extension to Chrome called Facebook Nanny: https://chrome.google.com/webstore/detail/facebook-nanny/gkpjofmdbabecniidggbbicfbcmfafmk
This is a nice little plugin in that unless you have notifications from Facebook, a message will show up instead disabling use of Facebook. If you’re finding yourself going on Facebook more than going on with your productive day, you’ll find some great use to this. Now, if there was a way to tweak it and make it so it’d display the message no matter what, you could have some fun with people at your work.
This isn’t something people should really depend on working, unless it uses the FB API to see if there’s notifications (which I doubt). As evident by the Social Fixer plugin, Facebook likes to break it’s design on purpose so things like Social Fixer doesn’t work anymore. But, regardless, this can be quite useful in trying to to get back into the swing of things, and get more work pumped out before your next deadline.