If you were trying to hit the easter egg you have to put it in the query string, not just as a sub-url.

Yeah, I noticed that, but there's definitely an ugly page there that I thought you might want to fix.

What is wrong with that 404 page?

It's a 404. Form follows function. I prefer it to a prettified version, honestly.

"Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request." suggests that something is amiss.

I'm not a big fan of overboard, fancy graphics (just look at my sites), but just a little bit of looking nice goes a long way.

It's a standard Apache error. No big deal.

Really, if the user hits a 404 then something has gone badly wrong and I think it's appropriate for them to get an ugly message.

If it is a 404 page, do not assume that it's something the user has done intentionally. Links change, sites link wrongly. Link-shit happens.

If you really want your users to be helped by your site, even when they've ended up somewhere they probably shouldn't have gone, you need to have a basic 404 error page which gently describes that the page doesn't exist and contains a link back to the home. Not everyone using a website will see "404" and understand what it is, and without a link back to the main site, a user (potential customer) is lost.

Yes, I know it's a standard Apache error (I know a thing or two about Apache). What you are apparently not seeing is that there's an error when trying to handle the 404 with the ErrorDocument directive, which indicates that their configuration needs a bit of tweaking.

Even for 404 errors, it's pretty standard practice on corporate web sites to include at least some of the main site's look and feel, with a link back to the main page or something.