I may have shared a similar tip before, but this one is always useful. Some folks feel like the Ribbon is just a little too bulky, and the DownloadSquad shares a couple of ways to keep it hidden but accessible.
From the article:
To collapse it, simply double-click one of the Ribbon’s tabs, such as “Home”. The whole thing will instantly shrink down to the line of tabs. Clicking a tab will temporarily expand it back. If you’d rather do the same thing using the keyboard, simply hit Ctrl+F1 (that’s what I normally do).