There are some great novel recommendations here, but I wouldn’t say that most of them are lesser-known.
What are your recommendations?
As for me, I’ve exclusively read well-known novels, except if you consider someone like Alfred Bester obscure, for example.
One exception: Misha Burnett’s Endless Summer: Twelve Strange Tales of Mankind’s Future. It’s a collection of exceptionnaly well-crafted stories. It ain’t a novel, though.



This was assigned reading and the instructor had us guess about the year of publication also. Interesting to me that the question is still being asked, since it was four decades ago when I read it.
Interesting. I only discovered it a year or two ago, and not because of school or anything. I believe I saw it mentioned in a comment on Hackernews, and and the commenters praised it a lot there, so I read it.