There's one HN custom I really adore, and it's the random, interesting wikipedia articles that are posted and sometimes upvoted to the front page. cf: https://news.ycombinator.com/from?site=wikipedia.org
This curated discovery of some obscure facets of humanity. Picking random articles from that list, for example, on the game Nomic; the Pineapple Express term in meteorology; or the British plan to build an aircraft carrier out of pykrete, which in case you didn't know is a mixture of paper and ice.
I was planning to try to help kickstart this here by posting articles with a special tag but I'd actually like to get people's thoughts on this, and if it's something others are interested in, suggest adding a ~wikipedia tildes to encourage this here more officially.