It seems that most recomendations fall in the sci-fi genre. I'll add my personal favourite: Stanisław Lem (the author of Solaris). The Star Diaries and Cyberiad are a lot of fun mixed with really interesting ideas. But if you want to read a very actual story, including an anticipation of the Internet, take a look at this 1961 story: http://en.wikipedia.org/wiki/Return_from_the_Stars
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