I recommend pretty much anything by Jack Vance. If you like fantasy settings, read "Lyonesse", "Cugel's Saga" and "Rhialto the Marvellous". If you like sci-fi settings, try "Araminta Station" , "Night Lamp" and "Alastor". For a quaint mix of the two, try "Emphyrio" or "Languages of Pao". Vance wrote a bunch of great stuff, so if you like his first book, you have heaps more to look forward to.
Also "Name of the Wind" and "Wise Man's Fear" by Patrick Rothfuss are pretty good.
I also second "Ender's Game".
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