XKCD is a very intelligent comic, and pretty much every post has something to do with science. Every so often there is a large format comic explaining some macro scientific concept. Today's is talking about depths, likely brought about by James Cameron's recent dive. It does a pretty good job explaining how massive the ocean is. Be sure to click the image for an expanded version, and read all the fun facts (a few are jokes, but some good trivia in there!).