Is email a distraction? SelfControl is an OS X application which blocks access to mail servers and websites for a predetermined period of time. It can not be undone by the app or by a restart – you must wait for the timer to run out. More info »
It is possible to use SelfControl as an automatic internet filter, which can run at specified times/dates. See the Mac OS X Hint here: http://hints.macworld.com/article.php?story=20100801214648362
Pick a reason for reporting this application below and then give us some more details in a few words. Please include URLs and so on if relevant.