1) I may not be a Silicon Valley technocrat, but I do have a strong understanding of core computer science and programming. Part of why I'm here is to further that knowledge for use in both my personal and professional projects.
2) Links cover much more than just geeky technobabble. I enjoy reading a variety of topics from statistical discoveries from big data analysis to political thought pieces to websites designed purely for fun to links about new services. The range of topics is fairly robust and it excludes the stuff I don't care about (sports, celebrity gossip, etc.)
3) I care deeply about personal security and there are solid discussions here semi-regularly about that.
4) Opposing viewpoints. Many politically related comments here are on the liberal/democratic side of the fence. I'm more of a socially libertarian but fiscally conservative person. I like coming here to expose myself to different opinions and, more importantly, the thought processes behind them. I consistently evaluate those ideas to see if they have merit and whether or not they fit into my value system. In is my belief that if there is a well-reasoned argument that contradicts my own, this is one of the places I will find it. I also post my own thoughts here to see how they land with the crowd. More often than not, they resonate. If not, they at least don't get downvoted or piss anyone off. This tells me that when you are talking about intelligent, reasonable, normal people there is more common ground between the various ends of the political spectrum than I had imagined. Finding this common ground and gauging the reactions to politically related material is one of the most important functions of HN for me. It helps me grasp what's going on in other people's minds who aren't just blindly supporting a political party.
5) Comment quality is far above nearly all other sites. This is, almost without exception, the only place on the entire internet I post anything public. I don't use social media and almost never comment on any other forum or public article online.
6) The simplistic design. It's fast, straightforward, and bullshit free. No ads or third-party scripts.