SuperScholar lists the most influential books of the last 50 years. Note that this is not a list of the most enjoyable books, but the books that had most influence in society.
Books from this list that I plan on reading in the near future include:
Chinua Achebe (1958) Things Fall Apart
Toni Morrison (1987) Beloved
Allan Bloom (1987) The Closing of the American Mind
Umberto Eco (1980) The Name of the Rose
Daniel Goleman (1995) Emotional Intelligence