If you want to have more peaceful night sleep when working on Ubuntu or other Debian based Linux distro, be sure to have gtk-redshift installed.
It is a little program that simply changes the color gamma of screen and makes your screen look more reddish at night. According to many scientific research done on how we humans react, whether using computer late at night. It is concluded that less bright colors and especially reddish color gamma relaxes our eye strain and thus makes it easier for us to get a sleep quickly once in bed. gtk-redshift is available in latest Ubuntu 12.04 as well as on other Ubuntu derivatives (Xubuntu, Mint Linux) etc.
Easiest way to install it is via respective GUI Package Manager or via good old Synaptic (GUI aptitude frontend).
I personally prefer to always install Synaptic on new Desktop Linux PCs, use it as package GUI frontend, for the simple reason it offers one very similar "unified" package Installer outlook across different Linux distros.
The quickest way to use GUI version of Redshift is to install with apt:
root@xubuntu:~# apt-get install --yes gtk-redshift
To further use it it needs one time to be run with color gamma paraments, launch it first time via terminal with:
user@xubuntu:~$ gtk-redshift -l 52.5:13.4
It is a good idea to make a tiny shell script wrapper with good settings for gtk-redshift and later use this shell wrapper as launcher :
root@xubuntu:~# echo '#!/bin/sh' >> /usr/local/bin/gtk-redshift
root@xubuntu:~# echo 'gtk-redshift' >> /usr/local/bin/gtk-redshift
root@xubuntu:~# chmod +x /usr/local/bin/gtk-redshift
From then on, to launch it you can directly open it via terminal
To make the program permanently work, make it run via respective GUI environment startup . In GNOME add it start-up from:
Important note to make about gtk-redshift is that on some older monitor screens, very early in morning the screen becomes too red, making screen look like displaying on very old long time used CRT monitors. For people working in fields like; Web Design, Architecture, or any drawing twisted colors effect will be annoying and will probably interfere with your perception of colors. However for programmers, system administrators and people who use computer mainly for typing and reading gtk-redshift is huge blessing.