Some which I have re-read recently and still enjoyed: William Gibson's Sprawl trilogy Frank Herbert's Dune series Isaac Asimov's Foundation series Frederik Pohl's "Gateway" Robert Heinlein's "The Moon is a harsh Mistress" Some which I remember liking when I read them many years ago as a teenager: E.E. Doc Smith's Lensman series David Brin's Uplift series Peter F. Hamilton's Greg Mandel trilogy and The Night's Dawn trilogy Orson Scott Card's "Ender's Game" George R. Dickson's "Dorsai!"
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