I was looking at this question, and intentionally loaded two copies of the page (into two different tabs). Loading results were slow, and one of the tabs showed an error message.
It was about 12:45am Pacific Time. The error message was basically something like "Superuser is down for maintenance. Usually maintenance is short. If maintenance will be longer, then status will be tweeted."
There were also a couple of graphics. One was a comic, titled, "How I made a Hacker out of a Slacker". I realized that my exposure to this graphic may be a result of an experience that I am unlikely to reproduce at will, and the comic (for some reason) seemed vaguely potentially interesting, so I decided to take the opportunity to read this comic.
I read the first panel... something about a Palm (Pilot) not working...
but then... SuperUser refreshed the page, showing the question that I was requesting earlier.
Okay, after a bit more Google Searching, I did find a copy of the comic. So I've now been able to finish it. Still, is this some normal part of an error page (or was SuperUser just acting really weird... in need of maintenance)?