Today's xkcd comic is...huge. Enormous. Seriously, the thing goes on for pages. It must have taken creator Randall Munroe forever to draw it all out.
But hidden in the huge map of the world as he sees it are a bunch of gaming references, like Mario up top. Or Oregon Trail below, which brings me back. Pokémon was probably a must. And I insist there's some BioShock reference in the pirate ship. At least a tiny one.