Classics aside (LoTR, Thomas Covenant, Gormenghast, Lankhmar, Earthsea), the book that I read recently and that really blew my mind is Jacqueline Carey's duology The Sundering (Banewreaker and Godslayer). At first I was put off by the fact that it is essence the retelling of the LoTR story from the point of view of the bad guys, but when I saw the recommendation on GRRM's blog. I read it. And I was blown away. The book is much more than what i thought it would be. First and foremost I loved the characters (hence my nick); Ms. Carey's writing style is exquisite - perfect for epic fantasy - the description of tragic events in the ending nearly brought tears to my eyes. Also, it was very thought-provoking. Long after, I was thinking about the book and the fact that history is written by the winners so who can be sure what is the real truth. It still occupies my mind.