All right. Who broke Catbert The Great?
I was actually looking for something else, and remembered that @catbertthegreat had commented on it, or so I thought. I hit the user tab, and then the votes that he'd cast, for Questions. On or around 12/01/2009, all questions that he voted on are doubles. That is to say, if you click on the double arrow that takes you to the last page (currently 8 of 8), every question he voted on appears twice. It's true on page 7 as well. The last question that is doubled appears split between page 7 and page 6:
I can't find another user that this has happened to, but I only tried for a short while. This is, hands down, one of the strangest bugs I've seen. Every time I think the site's starting to get a little boring, you hand me a gift to keep my fascinated.