[Doctor Stochastic]

As do Alice in Wonderland and Through the Looking Glass, althougn these are more akin to fantasy.

[Condorman]

And don't forget Around the World in 80 Days, and Shelly's Frankenstein as early examples of SF. (Although Saberhagen's The Frankenstein Papers is a pretty amazing retelling of Shelly's original work.)

BTW, have either of you read Verne's "lost" novel Paris in the Twentieth Century? Apparently it is a distopia story, and pretty dark, as well. From what I've read (and from a "History of SF" class I took in college), Verne's editor lightened his original stories considerably, and the recently discovered manuscript bears this out.