A number of people objected that http://xkcd.com/1000/ was really the 999th comic, citing the absence of comic #404.

However, I have always been of the opinion that http://xkcd.com/404/ is an actual comic, if a slightly avant-garde one. I actually went out of my way to modify the 'random' button to include it, but that annoyed too many people—most of whom reasonably assumed it was a bug—and I eventually undid it.

Speaking of which, this is my new favorite comic:

http://www.mezzacotta.net/postcard/?comic=1

I particularly like the video game.
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