SelfControl for Mac comes as a software stand-in for when your own personal self-control needs some assistance. You can use it to block access to domains for short or extended periods of time.
SelfControl for Mac requires no installation, just download and launch. While there is no Help file or any kind of tutorial, the basic interface, consisting of a button to add domains, a slider bar timer, and a button to start the timer, is easy to comprehend, and setting up the app is a snap. We added several Web sites to our blacklist and set the timer for 15 minutes. Once the timer was on, we could no longer access the sites on our list until the timer was done. Even when we closed down the application and deleted it from our Mac entirely, we could not access sites on our blacklist until the 15 minutes were up. The software claimed to be able to block mail servers, as well, though we were still able to receive mail after blocking ours. It did not appear that there was a way to use wildcards to block multiple sites, but if you're stuck on a few sites and need to force yourself to take a timeout, Self-Control will get the job done.
SelfControl for Mac offers an easy but effective solution for anyone who can't seem to get off of Facebook or other time-sucking sites.