I would also like this, though I was thinking of it as a feature for gnus.el, an emacs subsystem with existing backends for usenet, rss, email, and a few other things.

I’ve never used anything like that and don’t feel like I’ve missed anything. I do have a contactless credit card. It works out about the same way, I think.

It would be cool if there was a way to move a post from one community to another, so the poster gets notified and maybe the old link redirects. Some BBS systems support this.