[Lord Kodos]

Well if we are doing books...

Anything by Niven, but mostly the Ringworld Quartet(IIRC, a new one is coming out soonish!)
The Ender Quartet
Foundation series
Anyuthing Asimov.

And although its not a series, I think it deserves mention as it is IMHO the greatest video game ever. Period. Final Fantasy VII. Rivaled only by the Marathon Trilogy and Halo. Thank you! Goodnight new york!