I have recently been reading the works of the science fiction author Vernor Vinge. Dr. Vinge was a computer science professor at San Diego State University, but has retired. His writing has a very positive view of science and mankind, and it could be considered "libertarian" (in a similar way to Robert Heinlein) in that its characters recognize that freedom is a necessary precondition to thought and action. In general, I enjoy his writing style: Clever, witty, focused on showing visions of the future (rather than explaining). I think that he has an uplifting view of humanity, and makes honest and interesting speculations the future.
Books (in the order that I read them):
A Fire Upon The Deep - A story about intragalactic civilization in the far future. By its nature, such things require a vastness about them that makes it difficult to really work the characterization and plot. Mr. Vinge worked that by providing a sub-story involving a pre-space-travel society.
The Collected Stories of Vernor Vinge - Excellent set of short stories. Fun, thought-provoking, and usually well-written.
A Deepness in the Sky - One of the top two favorite novels by Vinge. Two competing groups of space travelers (one a totalitarian dictatorship and the other from a free-trade society) visit a pre-space travel alien civilization.
The Peace War - A group of techie revolutionaries fight against a world-wide dictatorship, with the primary weapon (on both sides) being a stasis field generator ("bobbler").
Marooned in Realtime - This one could be my favorite. It is a mystery story, set in the far future (in the same world as The Peace War), where the majority of humans have disappeared. The survivors, with varying levels of technology, have to rebuild civilization. One of the remaining humans, a policeman, is tasked to determine who murdered one of the leaders.
Tatja Grimm's World - Bordering on fantasy a bit. A talented woman of unknown origin rises through a medieval-level civilization, and eventually makes contact with aliens.
Rainbow's End - The most recent of Vinge's books, and set in the near future. A group of schoolkids use commonplace (for the near future) technology to foil a biowarfare plot. This book touches on a lot of very relevant topics for our age… the effects of rapidly growing collaboration technologies, future user-interfaces to such technology, the interplay of our vast technological capabilities and the ability of (even low-resourced) individuals to cause great damage.
One of the recurring themes in Vinge's work is the concept of the Singularity . This concept suggests that advances in science and technology enable faster advancement of science and technology, such that there will come a point in time in which change is happening so fast that it is impossible to predict what is on the other side of it. Some suggest that this includes the development of super- (or trans-) human intelligence. Vinge puts this point somewhere around 2020 or so, as that is the point at which computer hardware will have about the processing capability of a human (given current technology trends). (This "the end is nigh" idea has resulted in the Singularity being described as "the Rapture for nerds".)
Personally, I enjoy reading stories in which people grapple with these the issues of the near future, and Vinge writes believably and well.