[JSWolf]

These are so far the books with 3 nominations... I'll be updating this as needed.

Anathem by Neal Stephenson
Stephenson conjures a far-future Earth-like planet, Arbre, where scientists, philosophers and mathematicians—a religious order unto themselves—have been cloistered behind concent (convent) walls. Their role is to nurture all knowledge while safeguarding it from the vagaries of the irrational saecular outside world. Among the monastic scholars is 19-year-old Raz, collected into the concent at age eight and now a decenarian, or tenner (someone allowed contact with the world beyond the stronghold walls only once a decade). But millennia-old rules are cataclysmically shattered when extraterrestrial catastrophe looms, and Raz and his teenage companions—engaging in intense intellectual debate one moment, wrestling like rambunctious adolescents the next—are summoned to save the world.

Under the Dome by Stephen King
"The town of Chesters Mill (pop. approximately 2000) is suddenly cut off from the rest of the world by an invisible barrier, preventing anything other than a small amount of air from passing through. What follows is mostly told from the perspective of Dale "Barbie" Barbara, a former Army lieutenant. After "Dome Day" as it comes to be called, the town quickly collapses into anarchy, as a small war breaks out between the power-hungry second selectman James "Big Jim" Rennie, and a portion of the townsfolk. Resources quickly begin to dwindle, and many begin to resort to monstrous acts of violence to survive."

A Fire Upon the Deep by Vernor Vinge
Subjects: Science Fiction, Science Fiction And Fantasy, General Fiction
Description: After a spaceship crashes on an unfamiliar world, a rescue ship races against time to rescue the downed ship's only survivors -- two children -- and retrieve the weapon required to prevent the destruction of the universe. This special eBook edition adds hundreds of annotations from Vinge which were written during the time of his original composition of this groundbreaking Hugo Award … more »winning novel. A Fire Upon the Deep won the prestigious Hugo Award when it was first published.

Inherit the Stars by James P. Hogan
The man on the moon was dead. They called him Charlie. He had big eyes, abundant body hair and fairly long nostrils. His skeletal body was found clad in a bright red spacesuit, hidden in a rocky grave. They didn't know who he was, how he got there, or what had killed him. All they knew was that his corpse was 50,000 years old—and that meant that this man had somehow lived long before he ever could have existed!

The Machine Stops by E. M. Forster
The Machine Stops is a science fiction short story by E. M. Forster. The story is about a world in which many humans have lost the ability to live on the surface, and live underground. The story predicted a few technological and social innovations, such as the cinematophote (television) and videoconferencing.