Just came across this the other day. It is precisely what I had been looking for for some time now and had been thinking of perhaps trying to put together some such thing myself (since federated alternatives to Twitter and Facebook, such as Mastodon and Diaspora don't quite cut it). So, Scuttlebutt (which is slang for gossip among sailors) was created by Dominic Tarr, a Node.js developer, designed for off-grid living, disaster resilience and such and is very minimalist. It's a gossip protocol built around the natural ways communities and human interaction take place. Scuttlebutt's architecture is built so that the network connections accurately represent the social graph and word of mouth, with peer-to-peer infrastructure accurately matching peer-to-peer interactions. It makes communication and the spread of information highly resilient, bringing improvements to freedom of speech with modern information technologies.
Unlike Bitcoin and BitTorrent in that the Scuttlebutt protocol has no "singleton components" in its network — there's no bootstrapping servers, no canonical ledgers, etc. It's also different from federated social networks like Mastodon, Diaspora, GNU social, OStatus, etc. in that it's completely decentralized and there's no dependency on third-party servers and ISPs, which makes it possible for admins to abuse their influence and power (through content policies, privacy violations, censorship, etc.) There are Scuttlebutt servers known as "pubs", which are set and run by community members and facilitate information to spread faster and globally, but are not absolutely necessary and dispensing of them only slows things down.
Structure of how identity and diary entries / feeds work in the Scutterbutt protocol. Source: staltz.com
In Scuttlebutt, the “mesh” suffices. With simply two nodes (computers or devices), a local router and electricity you can exchange messages and diary entries between the nodes with minimal effort and no necessary technical skills. Each account in Scuttlebutt is a diary (or “log”) of what a person has publicly and digitally said (but can also optionally be private). As those people move around between different WiFi and LAN networks, their log gets synchronized between different computers and so digital information spreads around. Each Scuttlebutt account is comprised of two things: an append-only diary and private/public asymmetric cryptographic keys (an account’s identity being its public key, just like in Bitcoin and Ethereum).
Scuttlebutt uses a stand-alone app right now (a simpler and a more advanced version, available for Linux, Mac and Windows), as well as an Android one and also has a Firefox add-on. You can read the protocol specification in more detail here.
I think we really need alternatives of the sort and maybe even more urgently than we think, just as we largely don't realize and are unaware of the damages current social media in its centralized Web 2.0 incarnations of digital feudalism has done and is doing (which Shoshana Zuboff, for one, has investigated in much depth and detail in her "The Age of Surveillance Capitalism"). I myself do notice an emergent trend of returning to the simplicity and calm, distraction-free minimalism of the earlier Internet, defined by protocols like USEnet and IRC — one ironically much cozier and much more "social".
Additionally, I myself have been thinking about the possibility of adding modules to such protocol/network to politically instrumentalize it on a local/municipal level — with things like quadratic voting, liquid democracy, polls and referendums and even possibly implement DAO-like community-run treasuries and funds. This is where blockchain may come handy, but otherwise as a whole, blockchains are highly inadequate and poorly suited as the foundation for social apps of the sort. I hope we've come to understand this fact and not buy into idiotic ICOs and ridiculous ideas any more.
Either way, the Internet is being re-fashioned, re-structured, re-architectured and re-build — it's like the early days in many ways, with a lot of speculation about a connected world. Only this time it must be driven by urgent necessities, given the issues and problems before us on the horizon.