After years of kinda sorta wanting to read it, but always being skeptical, I bought Venus on the Half Shell -- the book Philip Jose Farmer wrote under the pseudonym of Kurt Vonnegut's pulp fiction alter-ego, Kilgore Trout -- for three dollars. (Cover images here. I have the really filthy one.) According to the interview quoted here, Farmer intended to write a whole series of these, but Vonnegut stopped him after the first one.

The entire book revolves around what many people would say is the central question of human experience: "Why are we born to suffer and die?"* It's a subject I never get tired of.

Now, Venus on the Half Shell is no classic. But it's such a bizarre merging of fiction and metafiction that it's really worth reading, particularly for any Vonnegut completist -- the style is such an intentionally perfect-but-imperfect approximation of Vonnegut's that it's basically the closest you'll ever get to reading a book from an alternate reality.

It's a rather strange literary experience.

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*For what it's worth, I'd say the central question of human existence is actually "How is it that there is a universe in which we might be born to suffer and die in the first place?" Once we get that worked out, the rest of our questions, including the first one, should all fall into place.