You probably know that spinning the mouse wheel will scroll up and down the page, but you may not know that it can also zoom in and out for you. Simply hold down the Ctrl key and spin the wheel slowly. Your view of the screen will get larger or smaller depending on which way you scroll.
Note that it doesn’t affect the printout of the document, only what it looks like on the screen.
This works for all Microsoft Office apps except Access (Word, Excel, PowerPoint, Outlook, and Publisher) and for most other programs.