Hah! I learned of Anna's a few months ago. I posted a slightly snarky comment on the lack of an explainer and got downvoted to oblivion

https://news.ycombinator.com/item?id=46169388

  >>  You know, it wouldn't kill them to add some fucking details to the main page rather than making you dig for it. The TL;DR:

  WTF is a Anna's Archive: Hi, I’m Anna. I created Anna’s Archive, the world’s largest shadow library. This is my personal blog, in which I and my teammates write about piracy, digital preservation, and more.

  WTF this post is about: Exclusive access for LLM companies to largest Chinese non-fiction book collection in the world.