For fun SciFi I second the Hal Spacejock series, there's a bundle of the first 4 books for $9.99 available at his website
Turing Evolved by David Kitson is a very good Science Fiction novel about AIs and their interactions with each other and humans. It's got a nice dose of romance as well as action. Available for free at Smashwords
Peter Watts' Rifters trilogy is very good, but darker, Science Fiction.
They're free as well on his website