I'm a huge sci-fi/fantasy fan, especially post-apocalyptic fiction. 1. Dies the Fire by S.M. Stirling 2. Dune by Frank Herbert 3. A Song of Ice and Fire by George R. R. Martin 4. The Hunger Games by Suzanne Collins 5. Speaker for the Dead by Orson Scott Card
I liked the sequels more than Ender's Game, actually. In Speaker for the Dead, he is an adult, and traveling through time in hyperspace, from planet to planet, performing rights for the dead. Very good read, and an entirely different book than Ender's Game. In fact, I think the series keeps getting better as it progresses. Xenocide, the 3rd book in the series, is another of my sci-fi favorites.
I'm also really interested in sci-fi ever since reading Fahrenheit 451 by Bradbury. I've wanted to read Isaac Asimov and more sci-fi for some time but have never gotten around to it.