|Apollo 15 (Source)|
For those who need a dose of "hard" SF, the Atomic Rockets site is a goldmine. The site is presented as a resource of materials for writers of science fiction, mostly focusing on space travel. It also serves as a wonderful repository of quotes and excerpts from the great science fiction writers--Heinlein, Asimov, Piper, Niven, etc. As you might expect from its title, the majority of articles pertain to space travel and space craft, but there are also sections on games, languages, aliens, intersteller society, and so on--all from a more "scientific" point of view.
Of course, the weakness to a purely scientific approach is that it rarely predicts major breakthroughs--those leading to paradigm shifts. For instance, although robots and mechanical minds show up in some early science-fiction works, the idea of a generic programmable machine was overlooked. Similarly, even well into the 70's and early 80's, the impact of small, personal computers was overlooked. H. Beam Piper's novel The Cosmic Computer sticks out in my mind as the epitome of this period. The protagonists are attempting to track down the greatest computer in the galaxy, and when they do so, it requires a specialist days to decipher the computer's calculations because the computer was unable to communicate except in some form of computer code.
Also, this site does not address issues of biotechnology and nanotechnology, being beyond its basic purpose which is, of course, rockets. Anyway, it is a fun sight to explore. Check it out.