If you’re at all interested in writing, or even simply better understanding the various forms of genre fiction, you will not want to miss the OC’s lecture on Advanced Scribbling 301 being conducted at his blog:
Comedy and horror are two sides of the same coin. Both depend on timing; both depend on setting the reader up for the emotional payoff; both deliver the ending with a twist. Twist it one way and it’s comedy: man slips on a banana peel, falls down, and loses his dignity. Twist it the other way and it’s tragedy: man slips on a banana peel, falls down, fractures his skull on the sidewalk and dies. Twist it a notch past tragedy and it’s horror: man slips on a banana peel, falls down, is impaled on a picket fence, and as he’s dying the psycho killer who placed the banana peel there in the first place emerges from the shadows to lick his dripping blood.
Me, I’m not so much of a fan of dripping blood. I went for comedy.
But, here’s another heretical little secret for you. Science fiction writers like to gas on about how SF is “the literature of ideas.” The more honest statement is that SF is the sanctimonious member of the horror, comedy, and adventure family. In short fiction especially, it is far more about setting the reader up for the emotional spike than it is about exploring any breathtaking new frontiers of speculative thought, and it’s far more acceptable to end the story with an ironic twist or a disquieting ambiguity.