I would add Permutation City. It's about: what's it like to be a digital person in a virtual world? What are the psychological effects of knowing that you're virtual; how do you experience time passing; what are the social implications of changing your appearance at whim, etc.

And, how do different interpretations of data compete to become "real"? For example, if you look at it one way it's a city, another way it's a collection of data cells to be colonized, etc.