Astonishingly, in the last few weeks, I've actually found time to read some-- gasp-- novels. In particular, I finished two books that probably belong in the "Hard SF" genre: A Darkling Sea by James L. Cambias and Lockstep by Karl Schroeder. Both Jim and Karl are people I've met many times at cons; I've enjoyed a lot of books by Karl, but this is Jim's first published novel (I think).
I'm lumping these together both because it's rare for me to get time to read, let along booklog stuff, but also because there's a sense in which they're complementary books: Both offer thoroughly fascinating far-future settings by exploring neat ideas on one are of science, but glossing over some others.
A Darkling Sea is set on Ilmatar, a Europa-like world a long way from Earth, on a human research station dedicated to studying the native life at the bottom of an ocean which is itself under a kilometer or so of ice. The crab-like native creatures have highly developed sonar senses, and survive by farming organisms that strain sulfur-based nutrients out of warmer water venting from the planet's interior. They have a rich and fascinating culture, operating at a sort of pre-Victorian level, and the Ilmataran side of the plot centers on some proto-scientists. On the human side, the plot follows the scientists in the research station, and the fallout when a grandstanding human reporter is killed in an encouter with Ilmatarans, triggering a response from a third race, the Sholen, who have taken it upon themselves to enforce a sort of Prime Directive for everyone. The Sholen have their own interesting biology and culture, though less developed than the Ilmataran.
Lockstep, on the other hand, takes place in an entirely human-derived future, when Toby McGonigal wakes up from cryogenic hibernation to discover that 14,000 years have elapsed since he headed out on a routine mission to explore a comet. He's revived in the Lockstep culture, where vast networks of interstellar trade are made possible by the practice of "wintering over": every colony participating in the 360/1 lockstep will spend thirty years in hibernation for every month that they spend awake; this allows travel between worlds to seem like a mere overnight jaunt: travelers go to sleep, travel at sub-light speed to their destination, and wake up for a month or so at the other end, then return to find the folks they left behind still in synch with them. It's a nifty idea, and the lockstep culture is worked out in some detail (including its role relative to the non-lockstep cultures of the "fast worlds" of the inner Solar System and other stars).
In both cases, the real attraction is the Big Idea behind the setting: the Ilmataran ecosystem and the lockstep culture. Other details are kind of fuzzy-- there's some sort of FTL travel in A Darkling Sea, but all that's really mentioned about it is that it's really expensive; and the perfect cryogenic hibernation technology of the locksteps is pure handwavium. But both of those core ideas are worked through in a thorough and thoughtful way, making them a pleasure to read about.
Both books also feature action-movie plots-- the human researchers on Ilmatar launch a campaign of resistance against the Sholen, and Toby turns out to be the key to a bunch of family politics in the lockstep, which soon has him on the run not knowing who to trust. And in keeping with the notion that science fiction is always really about the era in which it's written, both books include a good deal of political subtext that isn't all that "sub." Lockstep is probably the more polished of the two, as far as the plot goes, but that's not really the point of either book. These are both squarely in the Asimov/Clarke/Clement/Niven sort of tradition, where the plot is mostly an excuse to explore a really cool world. And the worlds here are, indeed, really cool.
So, you know, if that's the kind of thing you like, I'm fairly confident you'll like these. I don't always go for that sort of thing myself, but I enjoyed both of these.
These sound good. Will break out the Kindle...
Curious if you ever read Stephen Baxter? David Egan? Both get into the QM in their work, Baxter from a cosmological perspective and Egan from a more narrowly focused one.
Egan wrote "Quarantine" which is a neat idea, exploring the Observer Problem, and Baxter's stuff -- the Xeelee novels, for instance -- is more seriously cosmic in scope, even getting into ideas like how a wormhole might actually work and what the consequences would be, and even one novel that takes place in a universe with a G constant a billion times higher -- it's oddly fascinating to think that you could make stars with much less mass, that turn to balls of iron.
(I actually once tried a back of the envelope for the last one, but lacked the sophisticated math to know if you'd get that effect -- what about electron degeneracy? But I'm not a physicist).
Jesse @ # 1 - Uh, do you mean Greg Egan?
@Pierce R Butler -- Yes I stand corrected! Stupid memory. :-)
I'd put Anderson ahead of Asimov in that set, and there were actually several others  participating in the 1960s and 1970s game of worldbuilding. And it was a game -- they were informally competing in it, complete with mutual critiques for the worlds as distinct from the stories.
Oddly enough, Clement seems to have been something of an outsider to the whole thing despite putting many of the others into fits of inferiority-driven depression.
I'd be more explicit on this, but my collection of 50s/60s magazines are in storage right now. Sorry.
 Including one of the first stories I'd ever read by George R. R. Martin, After the Festival. The world was in many ways more memorable than the story.
@DC - funny, I have a pretty complete run of Asimov's Science Fiction from about what, 1990 to '98 or thereabouts. I'd have to look it up but that's where I first ran into the Song of Ice and Fire world. As I recall he didn't organize it as POV chapters -- rather he sort of strung together the POV chapters as they are presented in the book. I always felt that you cold do that and have pretty complete novels (and in some ways it might have been an experiment not unlike what Orson Scott Card did with his Ender books).
Speaking of which -- I know there are loads of problems with Card. I have problems with Mr. Card. But hey, the guy produced some good stuff in his day. there was a humanist in there once. (Read Pastwatch if you don't believe it).