The Long Ships by Frans Gunnar Bengtsson (NYRB Classics, $18). Humor, like salt, makes everything better. I consider it required seasoning for any piece of writing, which is why the first title in this list of my favorite unlikely comedies is this 1955 novel about Vikings. Frans Gunnar Bengtsson wryly captures the silliness of a world in which both the problems and the solutions are men swinging axes. A Confederacy of Dunces by John Kennedy Toole (Grove, $16).