Alan and his group joining YC is the most mind-blowing thing to happen (for me) since I started working on HN. No one has influenced me more in thinking about computing, and his tireless work in talking about computing history (especially the work and culture around ARPA) is a true service. Watching his talks seems to be the only easy place to get that information, and when you start doing it it's like one of those dreams where you enter into a wing of your house that you didn't know existed.
Edit: One of my dreams for HN is for this community to become active in recovering, learning, and extending the computing culture that Alan talks about, which is so much more satisfying than the morass of complexity we mostly find ourselves bogged down in.