Open Library
Sci-Fi
The future, written before it arrives.

The Gods Themselves
Isaac Asimov

Ringworld
Larry Niven

The Door into Summer
Robert A. Heinlein

A Dance With Dragons
George R. R. Martin

The Skylark of Space
Edward E. Smith

Black Canaan
Robert E. Howard

The Boys from Brazil
Ira Levin

The golden apples of the sun and other stories
Ray Bradbury

Gladiator
Philip Wylie

A Dream of John Ball / A king's Lesson
William Morris

The Amazing Maurice and His Educated Rodents
Terry Pratchett

Foundation and Earth
Isaac Asimov

Podkayne of Mars
Robert A. Heinlein

Never Let Me Go
Kazuo Ishiguro

Captain Underpants and the Perilous Plot of Professor Poopypants
Dav Pilkey

The Passage
Justin Cronin

One Shot
Lee Child

The High King
Lloyd Alexander

The Currents of Space
Isaac Asimov

The Stars, Like Dust
Isaac Asimov