I’ve spent so long checking the same web sites when I’m bored, I do it without thinking even when I don’t like the sites much anymore. I don’t think I want to block myself from them entirely, but it’d be nice if there was a proxy that kept me from visiting some more than two or three times a day.
@arilin I literally have attempted to modify the hosts file on my Mac to block a couple of the sites like that for me. Seems Safari and Firefox ignore it now.

@kitana @arilin I've used Stay Focused extension (or similar extensions on other browsers) and it does exactly what you want. Between x and y hours you get ZZ minutes to go to your social sites. After that you are hard blocked and it is a pain to turn it off.

https://chromewebstore.google.com/detail/stayfocusd-block-distract/laankejkbhbdhmipfmgcngdelahlfoji?pli=1

StayFocusd - Block Distracting Websites

Boost your productivity by limiting the amount of time you spend on time-wasting websites.