This reminds me, I've wanted to make a bot to automatically upvote the most downvoted posts in a thread with the HN api. I'd call it anti-echochamber.HN or something like that.
I surf with showdead on and often find myself upvoting grey comments that don't seem factually incorrect or rude, perhaps just espousing an unpopular opinion. But man, a lot of grey comments are correctly moderated. I'd leave the most downvoted ones alone for sure.