Office 2007: The Quick Access Toolbar
To the right of the Microsoft Office 2007 button is the customisable Quick Access Toolbar containing the Undo, Redo, and Save commands. To customize the Quick Access Toolbar, click the drop-down arrow to the right of the toolbar. Click on More Commands to launch the Excel Options window. In the Customize category, simply select the commands (or icons) you wish to be displayed on the Quick Access Toolbar then click Add.