I just finished Anathem by Neil Stephenson and loved it. It's great if you want your mind twisted in a thousand philosophical directions. Plus, any fiction book that has calculus lessons in the back to help you understand the story gets my vote.
Non-fiction - psychology, modern political ideologies, sociology, history.
Fiction - Fantasy and science fiction classics.
As a body of work...
The Asian Saga by James Clavell is unparallelled .
Your representative owes you, not his industry only, but his judgment; and he betrays, instead of serving you, if he sacrifices it to your opinion.
- Edmund Burke
Right now I'm all aboard the Song of Ice and Fire (aka "Game of Thrones") express. I love it. Just starting the 3rd book.
Catch-22, Catcher in the Rye and nine stories, Note from the underground and the idiot. Grapes of wrath, the Bell Jar.
The Dark Tower, The Thin Red Line, shit like that.
The Rain Series by Barry Eisler is my favorite currently running series.
Fiction - The Dark Tower series, The Stand, Lord of the Rings, the Pern series, A Song of Ice and Fire, Kushiel's Legacy, Cloud of Sparrows, some manga (FMA, D.Gray-man)
Non-fiction - Carl Sagan's works, nature/ecology/evolution-related, bird-related, field guides...
To Kill A Mockingbird by Harper Lee
Anne Frank's Diary by Anne Frank