These are the top 106 books most often marked as "unread" by LibraryThing users as of October 1, 2007. I'm to bold what I have read, italicize what I started but didn't finish, and strike through what I couldn't stand.
Jonathan Strange & Mr Norrell
Anna Karenina
Crime and Punishment
Catch-22
One Hundred Years of Solitude
Wuthering Heights
The Silmarillion
Life of Pi
The Name of the Rose
Don Quixote
Moby Dick
Ulysses
Madame Bovary
The Odyssey
Pride and Prejudice
Jane Eyre
A Tale of Two Cities
The Brothers Karamazov
Guns, Germs, and Steel
War and Peace
Vanity Fair
The Time Traveler's Wife
The Iliad
Emma (It's in my PDA, and I'm reading it at work)
The Blind Assassin
The Kite Runner
Mrs. Dalloway
Great Expectations
American Gods
A Heartbreaking Work of Staggering Genius
Atlas Shrugged
Reading Lolita in Tehran
Memoirs of a Geisha
Middlesex
Quicksilver
Wicked: The Life and Times of the Wicked Witch of the West
The Canterbury Tales
The Historian
A Portrait of the Artist as a Young Man
Love in the Time of Cholera
Brave New World
The Fountainhead
Foucault's Pendulum
Middlemarch
Frankenstein
The Count of Monte Cristo
Dracula
A Clockwork Orange
Anansi Boys
The Once and Future King
The Grapes of Wrath
The Poisonwood Bible
1984
Angels & Demons
The Inferno
The Satanic Verses
Sense and Sensibility
The Picture of Dorian Gray
Mansfield Park
One Flew Over the Cuckoo's Nest
To the Lighthouse
Tess of the D'Urbervilles
Oliver Twist**
Gulliver's Travels
Les Misérables
The Corrections
The Amazing Adventures of Kavalier and Clay
The Curious Incident of the Dog in the Night-Time
Dune
The Prince
The Sound and the Fury
Angela's Ashes
The God of Small Things
A People's History of the United States: 1492-present
Cryptonomicon
Neverwhere
A Confederacy of Dunces
A Short History of Nearly Everything
Dubliners
The Unbearable Lightness of Being
Beloved
Slaughterhouse-Five
The Scarlet Letter
Eats, Shoots & Leaves: The Zero Tolerance Approach to Punctuation
The Mists of Avalon
Oryx and Crake
Collapse: How Societies Choose to Fail or Succeed
Cloud Atlas
The Confusion
Lolita
Persuasion
Northanger Abbey
The Catcher in the Rye
On the Road
The Hunchback of Notre Dame
Freakonomics: A Rogue Economist Explores the Hidden Side of Everything
Zen and the Art of Motorcycle Maintenance
The Aeneid
Watership Down**
Gravity's Rainbow
The Hobbit
In Cold Blood
White Teeth
Treasure Island
David Copperfield
The Three Musketeers**
There are a couple of book there that I just can't remember if I've actually read, or simply seen the movies/plays based upon them.