FastKeys is my favorite time saving tool. Take a look at this video I create to see why. It’s cheap, easy, and saves me endless cutting and pasting or hand typing, preventing typos.
It works in your email, Word docs, on websites (never type your address again!), and more.  Watch this 4 minute video and you’ll see how helpful and easy it is.  It’s only for PC, but for non-PC users, watch the video anyway to learn and then check out some of the Mac equivalents like TextExpander, aText or Alfred.