My husband found this Space Invaders post for me. This has been one of my pet peeves ever since I started editing 24 years ago. If you are a writer and want to impress an editor in a simple way, make sure you add just one space after each period -- this is the correct format! Really! And while I was checking out the Slate website, I came across this tongue-in-cheek piece about e-textbooks: click here.