Get Your Cheat Sheets Right Here
Over at MakeUseOf, they've compiled very useful keyboard shortcuts for Google search, Firefox, Gmail, Windows (including Word and Excel), and Mac OSX. They're not searchable (except once you download them as PDFs), but they are a great resource; In the Google page, I picked up a few tricks on how to search the web by the anchor text http://en.wikipedia.org/wiki/Anchor_text in sites, and learned that you can do math problems using the search bar.
I also learned that you don't have to rewrite lines that you mistakenly wrote with Caps Lock on in Word. (As a visual typist, this happens to me all the time.) Just select the text and hit Shift-F3. Pretty cool. At any rate, check them out and enjoy. If you find some that you really like, it might be worth making an abridged cheat sheet of your own--