If you can think of more, please leave a comment and let me know, I'd love to hear it.
What's Eating Gilbert Grape- The movie stars Johnny Depp, Juliette Lewis, and a young Leonardo DiCaprio as Johnny Depp's mentally retarded younger brother. The movie's pretty awesome, but I was really surprised to find it sitting in the stacks. First it was a book! Check it out -- same title, by Peter Hedges.
High Fidelity- Film starring the ever-adorable John Cusack and comedian sweetheart Jack Black. Originally, a novel written by Nick Hornby, who also wrote About a Boy (later ALSO a movie with Hugh Grant), and a book called Bong Water. I just included that last one because it's an attention grabber, and for the record, whenever I put it out on display, it goes rather quickly.
The Curious Case of Benjamin Button - Before the love story acted out by Brad Pitt and Cate Blanchett on the big screen, F. Scott Fitzgerald had written this average little short story based off of a quote by Mark Twain. It's not the love story from the big screen though, it's actually a little sad and depressing. But if you want to read it, it's in the public domain now, and you can read it here for free : http://www.readbookonline.net/read/690/10628/
The Green Mile- Stephen King. This man is a genius, and has had only about a bajillion of his books made into movies. This one isn't quite as creepy as a lot of his other novels, though, which is why it sometimes flies under the radar as a movie turned book. The movie is incredible-- with big shots like Tom Hanks, and the star of the show, Michael Clarke Duncan as John Coffey. He's absolutely fantastic.
The Shawshank Redemption- Following up on that, let's mention that Mr. Stephen Awesome King also wrote the novella "Rita Hayworth and the Shawshank Redemption", in a collection called Different Seasons, published in 1982. This became the movie we all know and love in 1994, and is by far the best prison movie ever made. (Side note- other movies from Stephen King books are Carrie, Hearts in Atlantis, Stand By Me, Secret Window, Pet Sematary, The Shining, 1408, Children of the Corn, and even the TV show, The Dead Zone -- these are just a few of the more impressive ones, but a full list can be found on his website at http://www.stephenking.com/library/video.html ).
The Prestige- I have to admit, the movie wasn't greatly known. It came out around the same time as another magician movie, The Illusionist (with Edward Norton). This movie stars Hugh Jackson (yum!) and Christian Bale, as two competing magicians. But I loved it, and that's why I thought it was useful to mention that it too was a book by the same name, written by Christopher Priest.
The American- The 2010 movie starring George Clooney was actually a book by Martin Booth first published under the title A Very Private Gentleman, but the book we own at the library was redubbed The American. I'm guessing this is probably because otherwise I wouldn't have picked it up, wondered about it, been surprised, and then posted this on my blog otherwise.
Sex and the City- Alright, if you're giving me a look as to "why is that on the list?" then just stop. I know, some of you know it, that Sex and the City was a book first. But not everyone does, so just chill. But although a lot of the characters appear, they aren't really the same as the TV versions, so it's a mistake to think they are. Just read the Amazon reviews, and they'll tell you. Bushnell has recently gotten further mileage out of Carrie Bradshaw with her newest book, The Carrie Diaries, the life of Carrie Bradshaw when she's first moved to the Big Apple.
True Blood- Stephanie Meyer is a hack compared with the intricacies of True Blood, and by that, I mean, the intricacies that Charlaine Harris created with her series, The Sookie Stackhouse Southern Vampire series. They are pure genius! It's a crime that Stephanie Meyer is so renowned as an author for creating her series, when Charlaine Harris is relatively unknown, yet she has so much fame for inspiring the HBO series, True Blood. I just recently got hooked, and it's my little guilty pleasure.