I stumbled onto a question that was deleted before I refreshed the page (read: could answer the question) and I noticed that we have an awfully boring 404 page. I feel that this is a grave problem!
This post may be a bit unnecessary, considering that we have the 404 Image Nominations question, but here it is anyways.
I've moved my suggestions into an answer, to clean up the question a little bit. Splitting the facts from the opinion.