Ever played some map, and you get your expectations subverted, not in a "This is better than I thought!" kind of way because you didn't think the .wad seemed that good at first, but also not "This is worse than I thought." where you're annoyed.

Rather, you're a bit baffled, and the way this subverted your expectations is funny to you, you laugh. Not necessarily the author's intent either, he didn't maybe intend for it to be a joke, but it's still funny.
Ever had that feeling?