This is wildly off-topic, but an idea caught my interest. I upvoted the parent of your comment to compensate for your downvote and it made me wonder how many other people have done the same. It put a bunch of thoughts in my head that I can't seem to form into coherent words, but those thoughts have to do with gaining quite a bit of comment karma from one person's accident, karma trolling, etc. I can't imagine that occurring on HN too any extent, but it's an interesting thought.

Tangentially, there are people in CS who study trust/reputation systems (like karma), and how to design those systems so that people want to participate and "do the right thing". Maybe related.