The list author says: "Science fiction writers are an earnest, earnest bunch. It's hard to bring us the high-tech weapons of the future, maniacal despots of the future, tragic bio-engineering of the future with anything besides a all-joking-aside approach. Once in a while an author views the future with a sense of humor. Here are some good examples."
"More fantasy, than sf, but Discworld is about a flat planet, so that makes it an exercise in otherworldliness. And it's very funny. This is the first in the Discworld series. Like with the Adams' books, try them all out."