Had a look at my bookshelf to see what I could find that was obscure, maybe these would be interesting:
First Contract (Greg Costikyan) - a book about the economics of first contact
John Courtney Grimwood (author) - science fiction, generally cyberpunk, told from the point of view of characters who don't understand the tehcnology, which gives his work a kind of mystic vibe. (Eg, Nine-tail fox is about a detective trying to solve his own murder)
Footfall (Larry Niven/Jerry Pournelle) - was a big release back in the day, but not so well known these days. Hard SF alien invasion novel (Independence Day might have ripped this off a bit)
The NASA trilogy (Stephen Baxter) - dark alternative future books, with bleak endings but great science. I think not so well known these days because of the bleakness, but that's also part of what made them memorable when I read them.
First Contract (Greg Costikyan) - a book about the economics of first contact
John Courtney Grimwood (author) - science fiction, generally cyberpunk, told from the point of view of characters who don't understand the tehcnology, which gives his work a kind of mystic vibe. (Eg, Nine-tail fox is about a detective trying to solve his own murder)
Footfall (Larry Niven/Jerry Pournelle) - was a big release back in the day, but not so well known these days. Hard SF alien invasion novel (Independence Day might have ripped this off a bit)
The NASA trilogy (Stephen Baxter) - dark alternative future books, with bleak endings but great science. I think not so well known these days because of the bleakness, but that's also part of what made them memorable when I read them.