Nod by Adrian Barnes, a novel recently nominated for the Arthur C. Clarke Award, can be downloaded for free until the 4th of August, courtesy of LondonCalling.com. In addition, if you're a UK resident you'll enter a giveaway to win a signed copy of the book.
This is the synopsis of the novel:
Dawn breaks over Vancouver and no-one in the world has slept the night before, or almost no-one. A few people, perhaps one in ten thousand can still sleep, and they've all had the same strange, golden dream. A handful of children still sleep as well, but what they're dreaming remains a mystery. After six days of absolute sleep deprivation, psychosis will set in. After four weeks, the body will die. In the interim, panic ensues and a bizarre new world arises in which those previously on the fringes of society take the lead. One couple experience a lifetime in a week as he continues to sleep , she begins to disintegrate before him, and the new world swallows the old one whole...NOD