Pomodoro Timer to help you focus
The Pomodoro Technique is a time management method developed by Francesco Cirillo in the late 1980s The technique uses a timer to break down work into intervals, traditionally 25 minutes in length, separated by short breaks. Each interval is known as a pomodoro, from the Italian word for 'tomato', after the tomato-shaped kitchen timer that Cirillo used as a university student.
With this extension you are able to customise the number of minutes you want the timer set to through the options page. You're also able to add tasks with the timer.