This is hard. So many choices...

Brideshead Revisited by Evelyn Waugh
A Prayer for Owen Meany by John Irving
The Awakening by Kate Chopin
Jane Eyre by Charlotte Bronte
To the Lighthouse by Virginia Woolf
Grendel by John Gardner
Christ Stopped at Eboli by Carlo Levi
She's Come Undone by Wally Lamb
The Romance of Tristan and Iseult
The Decameron by Giovanni Boccaccio
The Diary of a Madman by Nikolai Gogol
The Nose by Nikolai Gogol

Although everyone had such great choices, I've especially got to agree with Curtis on O'Henry's "The Ransom of Red Chief"--that's an all-time favorite of mine. And with Fox on Equus.

-acissej