There is a write up somewhere about this but I can’t find it right now…

There is a mastodon instance that bans the letter “e” https://oulipo.social/ it’s basically a writing exercise and challenge.

In response, https://dolphin.town/ is born. Where you can only use the letter “e”, even usernames.

Edit: found the write up! It even contains a brief interaction between users from both instances! https://interconnected.org/home/2022/07/12/folktale