There’s something of an art to a proper 404 page. You want to let the user know that she’s taken a bad step, and you want to help her find the correct path again. There’s a bit of professional pride in doing that, and still making a statement. Here’s the 404 page for this site. It’s pretty basic, frankly, when there are 404 pages that will generate haiku as part of the error message. But this page is, hands down, the coolest I’ve ever seen.