[elzr]

I second Karl Schroeder as a worthwhile SF author! His novels can be challenging but his ideas are unique and worth the price of admission:

* Ventus, his first novel, is about a world that turns accidentally alive (think Gaia) via nanotechnology.

* Lady of Mazes turns around how we could use (very advanced) technology to preserve cultures instead of undermining them.

* Permanence is about a star-faring civilization so advanced it doesn't need technology, it is technology, having perfectly evolved itself to its niche.

* The Virga series is set in a wonderfully imaginative zero-gee bubble-of-gas world, heated by an artificial sun --think of it as space with air!

Besides being an SF author, Schroeder is also a professional futurist. I recommend his OSCON 2009 talk,The Rewilding: A Metaphor, as a good introduction to his thinking.

https://www.youtube.com/watch?v=qb7pkohj6wE