I loved snow crash, but I really loved how stephenson literally killed cyberpunk at the beginning of the diamond age. I mean he literally killed the cyberpunk character at the beginning of the book. It solidified in my mind that the story was post-cyberpunk.
I've also thought a lot about the Gargoyles in Snow Crash over the past couple of years. Like Gibson's introduction of the term "cyberspace", Stephenson did an amazing job of predicting the gargoyle-effect.