Sunset - Dim Your Screen! at Mac App Store analyse

Sunset helps you to dim any of your computers screens, even more than possible with the built-in controls.
 Try it out, your eyes will thank you! 
Some scenarios: 
- You open your laptop late at night and are blinded, even though the brightness is at its lowest setting. 
- It is very complicated or impossible to change the brightness of an external monitor 
- If you have changed the brightness, the monitor starts to make an annoying beeping noise. - You dont want to wake up your seatmate on an airplane.
 - You want to reduce distraction in a meeting room or a lecture hall. Since Sunset uses a software-based approach to dim the screen, you can definitely circumvent the problem with the beeping noise at some displays. So in some cases, your ears will thank you too!