If you're dealing with multiple displays, you can setup a secondary screen that either is extended from the default screen (and you can set the appropriate direction) or to mirror the default screen.
From the graphics card tab, you can select the graphics card driver to use as well as specifying the video memory (if needed). A graphics card driver can be selected by the name of the driver (i.e. fglrx or vesa) or by selecting a driver based upon the graphics card's manufacturer and model. Both open-source and closed-source drivers are listed.
The location area allows you to create profiles for specific graphics card and screen configurations. While you're at the office, if you use a laptop with no external display you can create an "Office" profile and create another profile if you use another display when taking your laptop home or to the conference room. You can save and delete a location/profile at any time.
While displayconfig-gtk doesn't contain nearly as many features as the NVIDIA or ATI control panels for their binary display drivers, this is certainly a nice start for the Ubuntu team with RandR 1.2 integration. This Ubuntu utility contains the same basic options as what can be found in Fedora/Red Hat's system-config-display utility but in a more effective format along with the ability to create custom profiles. It would be ideal if displayconfig-gtk were able to integrate some of the features currently found in the open-source DriConf utility. DriConf is designed for DRI customizations such as application-specific settings, debugging, and performance management. Both displayconfig-gtk and DriConf are written in Python. For those petrified of manually editing the xorg.conf file for your display-related settings, you can find displayconfig-gtk installed by default starting with Ubuntu 7.10 Gutsy Gibbon.