If you are like me, and spend a greater portion of the day, and even night, sitting in front of the computer, then F.lux is a must have. Our displays are calibrated to look their best during the day. Unfortunately artificial light is quite different from sunlight. Natural light is more bluish whereas artificial light has a more prominent reddish tint. F.lux adjusts your colour temperature (tint) according to the time of the day. Just enter your location and select the type of artificial light you are using. F.lux will take care of the rest.
After using it for more than a month, I can confidently say that it indeed makes a difference. F.lux automatically calibrates the display temperature to make it easier on the eyes. The difference is even more prominent in a dark room. Before I started using F.lux, my eyes would begin hurting within an hour. F.lux even claims that it can help alleviate sleeping disorders resulting from staring at the screen for long durations.
The best thing about F.lux is that once configured, you can forget about it. It will run quietly in the background and keep doing its job silently. In my tests I found F.lux’s memory usage to be hovering between 2MB and 3MB, which is awesome. F.lux also comes with a handy disable for an hour feature. People who need to work with colour (such as web designers) would appreciate this since F.lux does tweak colour appearance to make the screen easier on the eyes. Give F.lux a try. Once you get comfortable with it, you are going to find it hard to stop using it.