I've just finished Neal Stephenson's Anathem. It's a whopper -- and probably a good advert for reading on a Kindle rather than lugging around an enormous (900+ page book). It's good. An amazing act of speculative imagination. Perhaps the story peters out a bit towards the end but like most good scifi the interest is to a large extent concerned with just living for a while in a different world.
Here he is discussing the novel and the genesis of the ideas behind it.
Anyhow, it is worth mentioning here because there is a lot of philosophy in it and a lot of ancient philosophy in particular. There's certainly a lot of Plato there (and just why there might be philosophical ideas reminiscent of Platonism in this world turns out to be part of what the book is about.) There's an appendix that does a good job, for example, of offering an alternative dialogue that makes the same point as the slave experiment in Plato's Meno.