WorkHourGlass

WorkHourGlass is a simple timer that allows you to manage easily your
working time. It times your work and breaks, making a beep sound at the
end of each so that you know you can take a break / return to your work.
There is also a change of color between break time and work time. Moreover, the times, sound and colors are customizable.

Actually, I found out that it is an basic implementation of the Pomodoro technique .