+4
Extend to programs rather than just chrome tabs
Not sure if this is even possible with a chrome extension - but for me, my distractions are usually more chat programs than anything, Hangouts, Telegram, Skype etc
Customer support service by UserEcho
(See also http://buildfocus.userecho.com/topic/1102942-add-a-i-failed-to-focus-button-to-handle-distractions-outside-of-chrome/)
I haven't installed anything in order to use Google Hangouts; it uses addresses like this one.