These are the top 106 books most often marked as "unread" by LibraryThing's users (as of today). Bold what you have read, italicize what you started but couldn't finish, and strike through what you couldn't stand.
I've put an asterisk by the books I have on my To Read pile.
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
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