Multiple Monitors Support in GNU/Linux

For the past two months, I've been busy configuring multiple monitors support for different machines. Instead of tweaking X's configuration file, I've found a easier way to configure it using aRandR, a frontend tool to XRandR.

Install the packages
$ sudo apt-get install arandr

Run it and configure your monitors layout. You can easily drag-and-drop and position your monitors.
$ arandr

To make the XRandR changes permanent and run it everything the X session start. Save the settings generated by aRandR in your home folder as $HOME/.xprofile.