Recommended Listening: "Exhalation" by Ted Chiang
We often break sci-fi into "hard" (stories driven by a novel scientific concept, often to the detriment of rich characterization; think H.G. Wells, and then try and name a character from one of his books) and "soft" (stories driven by the psycho-social impact of a scientific concept, usually rich in characterization, with the science often degraded to technobabel hand-waving--think of Bradbury, and then try to suss out if Fahrenheit 451 is supposed to be near-future or alternate history or what). Taking that "hard"/"soft" division to be a continuum, this is the most well-balanced SF story I've heard in *ages*. I'm really, really pleased that my iPod chose to shuffle it up to me this afternoon.
(You can listen to it at the above link, or read it here.)