Cold Turkey - Cold Turkey is a free productivity program that you can use to temporarily block distractions so that you can get your work done!
Be Focused by XWaveSoft - Simple Pomodoro timer in your Mac's menu bar
Stay Focused - More suitable with Google Chrome, this service enables you ensure you do not waste precious time on updating Facebook status or chatting with people.
Effortless - Stay focused and beat procrastination on your Mac.
Freedom.to - Freedom is a productivity hack that lets you block apps, websites or the entire Internet on iPhones, iPads, Windows and Mac computers.
Pulse.red - A powerful time tracker for those who appreciate simplicity