Am I the only Sci-fi nerd around here?
I've never read any of Asimov's writings before, but a friend of mine recommended me to read The Foundation trilogy, and after I started reading I got instantly hooked. For those of you who like "harder" science fiction, I highly recommend it.
It's different from most other Sci-fi books in the sense that instead of concentrating on a single story, it follows a certain state / world / society from the moment it's forged, through hundreds of years. That way, the books are divided into separate stories, each with its own plot and characters, and the only thing that's uniting them is historical chronology.
It's not so much an adventure book as a clever, quite-political science fiction story set in space. Not anyone's piece of cake. Nevertheless, I really liked it.