From where I stand, Hispanic and Slavic literature is fairly unknown and underrated on the other side of the pond. Ramón del Valle Inclán's "Lights of Bohemia": A great portrait of Madrid and the dirty guts of the Spain from 100 years ago, written in a gorgeously precise, dark and multifaceted range of vocabulary. Ortega y Gasset's "Rebellion of the Masses". It is centered in the individual "I am me and my circumstances" and its evolution since the enlightenment. Sapkowski's "Witcher". Look for a good translation, lots of Slavic mythology tidbits and wonderfully juicy curse words. Stanislaw Lem's "The Star Diaries". Nice if you like to fantasize about buying pieces for your spaceship in a shopping centre or think about chair-like aliens with 11 different sexes (in the book). Gabriel Garcia Marquez's "A hundred years of solitude". The book is all about "realismo fantástico", joining the real and imaginary words in an unforgettable blend.
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