Also from sircmpwn, there is a mailing list called free-writers-club [0] with quite a few introductory posts and blog links... post yours, everyone!

  Hello and welcome! This mailing list is for authors of technical blogs
  and other publications to support each other's work. Feel free to post
  questions, drafts for review, and so on.

[0]: https://lists.sr.ht/~sircmpwn/free-writers-club

The idea of a blogring is great - we need more of that imo.

It is on my wishlist for my blog but for now I haven't gotten around to it.

Also planned: some kind of list of the latest pinboard.in entries from certain tags.