One of the best ever SF books -- a game player from a utopian society travels to a cruel world with three genders to play the ultimate game.

Romantic screwball time travel comedy takes on Victorian manners and gender issues, chaos theory, history, literature, seances, WWII and cats, to name but a few. Light-hearted and brilliant.

The original cyberpunk novel still holds up.

Not just for children. Classic book about the evil of conformity and the power of love.

An asynchronous love story with time traveling as a medical condition. Sounds strange, but it really works.

Hyperion and the Fall of Hyperion are incomparable. Simmons combines religion, military history, the poetry of Keats, artificial intelligence, time displacement and more in this Decameron-inspired tale.

This and the sequel, Speaker for the Dead, are true originals.

A futuristic Arab country where people can modify their brains to accept "add-ons" and personality modules. A half-Maghrebi half-European drug-addicted hero living with a trans-gender stripper and searching for identity and faith. And absolutely scintillating writing. Also read the two sequels.

Varley is a master SF story teller and this is one of his most interesting. Gender switching, body modification, a computer that sees all and a sense of what the future may consider to be lost.

Reverse time travel tale in which a man, who may or may not have been one of Rome's greatest gladiators, is unearthed from the ice and reanimated.

If there is a better fantasy writer than J.K. Rowling working today, I'd like to find him/her. The whole series deserves to be on this list.