Retroshare kind of works like that, and it keeps the messages within your trusted network of friends. I think they have some articles about it here: https://re

Retroshare kind of works like that, and it keeps the messages within your trusted network of friends. I think they have some articles about it here: https://retroshareteam.wordpress.com/ https://retroshareteam.wordpress.com/ Bitmessage is also similar but sends the message to everyone.