I like all of Eliezer's fiction... if you want more like this, see the pseudo-sequel, http://lesswrong.com/lw/18g/the_finale_of_the_ultimate_meta_mega_crossover/ It is too insane of a story to recommend to most people, but assuming you've read Eliezer's non-fiction, you can jump right in.

Otherwise, just about all of Eliezer's fiction is worth reading, Three World's Collide is his best work of fiction.