Hard to tell you, the only real series I've read was Arthur C. Clarke's Space Odyssey quadrilogy.
2001: A Space Odyssey
2010: Odyssey two
2061: Odyssey three
3001: The Final Odyssey.
They were absolutely classic.
Another series by the Japanese author Suzuki Koji, was also thrilling.
[edit on 17/9/2008 by mandrake]