F.lux

F.lux screenshots

Adapts the color of your screen to the time of day to reduce eyestrain
Main Window
F.lux 4.7 : Main Window

Alternative downloads

Orbital Sunset 3D Screensaver and Animated Wallpaper
Get ready for a space trip where wind is solar and dust is cosmic.
1.1.0.7
LightBulb
Reduces eye strain at night by automatically adjusting display gamma.
1.6.3.6
FREE
Good Night PC
Small and effective utility to shutdown your computer.
1.9