Using a Mac laptop at night is great thanks to automatic-brightness controls and a backlit keyboard. Trouble is that sometimes even the lowest setting is too bright for midnight screen gazing. That's where Brightness Slider comes in.
It's a menu bar utility that lets you adjust the screen's backlight brightness. It gives you linear control over your backlight and lets you dim your screen even further than either the brightness keys or System Preferences allow you to go without turning off the backlight completely.
Unlike other applications that allow you to "dim" your screen, such as Sunset, which actually put a shade or dark tint over your screen to reduce perceived brightness, Brightness Slider gives you direct control over the actual backlight.
If you ever wish you had quick access to finer grained control over your Mac's backlight than the backlight keys F1 and F2 give you, or you want it just a little bit dimmer at night, then Brightness Slider is worth a free download from the Mac App Store.