Blindsight, the remarkable new sf novel from Peter Watts
is now available online, under a Creative Commons License, as is much of his backlist.
So far the buzz is that it's next year's Hugo Winner! Hardcover copies are selling out and readers are having trouble finding it, so his gesture is doubly appreciated.
edit: I should add that the hardback is going into a second printing, so if you wish to buy a physical copy, like I did, don't despair.