One of the gripes with the Unity interface of Ubuntu is that a lot of the configuration and settings are not accessible to the user. So, there are a lot of tools that have been written to expose such settings to the user for configuration. One of the most popular of these tools is the Compiz Config Settings Manager, which is popularly called CCSM.
CCSM can be installed from the Ubuntu repositories using the package name compizconfig-settings-manager.
Tried with: Compiz Config Settings Manager 0.9.5.92 and Ubuntu 12.04 LTS