Lots of people frequently need a GUI for their servers. I like to use mine without a GUI but even I have found many instances where one would be incredibly useful.
You can install the full Ubuntu desktop by installing ubuntu-desktop however, if you just want the basic plain Gnome desktop then consider running this…
sudo apt-get install xorg gnome-core gdm ubuntu-gdm-themes
Note: After you start Gnome it will display an error about fast user switching applet. Just tell it to delete the applet. You won’t be shown the error again.
For good measure I also installed firefox and synaptic.
sudo apt-get install firefox synaptic
