Iain M. Banks, The Player of Games

John Varley, Steel Beach

Roger Zelazny, Lord of Light

Zachary Mason, Void Star

Dave Duncan, Hero!

Jeremy Robert Johnson, Skullcrack City

Blindsight, Peter Watts

The Forever War, Joe Haldeman

Neuromancer, William Gibson

Under the Skin, Michel Faber

3 Body Problem

The Years of Rice & Salt by Kim Stanley Robinson. Epic alternate history novel beginning in the 1300s.

Rendezvous with Rama by Arthur C Clarke. A contained & very exciting adventure on a mysterious alien spacecraft. Classic SF.

Check out the front runners for a Hugo award this year:

Book of the New Sun. You're not gonna regret it.

Journey to the center of the earth from Julio Verne

I strongly recommend Ancillary Justice and the other books by Ann Leckie set in the same universe.

Asimov - Nightfall & Other Stories is probably the best short story collection I've read, if you're into that.