So ... The #Fediverse. I get that the Fediverse is not *one* thing but many things that use #ActivityPub. Much as the internet is not *one* thing but many things that use TCP/IP.
Mastodon is still, I think, the largest fraction of the Fediverse but as a Mastodon user, what powers does ActivityPub grant me? Do I magically have a "free account" on a Pixelfed instance? (yes, pretty much everything in the Fediverse is free, but you know what I mean). Does that other service "know" me?