1. A method for customizing the graphical user interface of a multi-function device, comprising the steps of: providing a multi-function device including a multi-function unit and a document server, the multi-function device having three or more built-in functions taken from a group consisting of: copying, printing, scanning, faxing, and e-mailing, and the multi-function unit having a graphical user interface originally configured to display standard icons representing the built-in functions, wherein the user may activate the standard icons to command the multi-function device to perform the associated built-in function; and customizing the graphical user interface of the multi-function unit, wherein the customizing step includes one or more of the following steps: modifying the image of at least one of the standard icons; adding an additional icon to the graphical user interface corresponding to an additional function activated on the multi-function device; and adding an additional icon to the graphical user interface corresponding to a modification of one of the built-in functions.