A new challenger to Twitter's walled garden: #Mastodon
"...Another program speaking the same protocol as GNU social made a huge splash this spring. It's called Mastodon, and its growing popularity was in part spurred by positive posts about it by Twitter users with large numbers of followers, like tech writer Sarah Jeong. That momentum is still strong..."
https://www.fsf.org/blogs/community/a-new-challenger-to-twitters-walled-garden-mastodon