Double-click the active tab to hide the groups for more room.
The Ribbon makes everything in Word 2007 nicely centralized and easy to find. Sometimes, however, you don't need to find things. You just want to work on your document, and you'd like more space to do that. So it's just as easy to hide the Ribbon temporarily as it is to use it.
Here's how: Double-click the active tab. The groups disappear, so that you have more room.
Whenever you want to see all of the commands again, double-click the active tab to bring back the groups.