When it comes to social media giants like Facebook and Twitter, you can be confident that if you’re not paying for the service, you’re not the customer — you’re the product being sold.

As public companies, they only need to please shareholders and they do that by turning the “engagement” knob up to 11, whether that means showering you with praise or filling you with rage.

Having so much power in the hands of so few companies is worrisome, whether they abuse it or not. The drumbeat for alternatives has been building, and there have been many attempts to build “the next Facebook.” The problem is that those attempts have tried to replicate the advertising model of the big guys. They can never capture enough eyeballs to sell.

(Remember Diaspora, Path, App.net, Peach, Vero or Ello? Me neither.)

What if there were social networks that were instead built and powered by unabashed idealism? What if the users made the rules, and Nazis and trolls were banished without controversy? And what if they were sustainable?

One such effort is Mastodon. It’s named for the rock band, not the extinct pachyderm. Born in 2016 out of the mind of a German college student, it is a clear descendant of Twitter, with a streaming timeline of posts (called “toots” rather than “tweets”), followers, favorites and reposts (called ‘boosts’).

But unlike many past attempts to make a business out of a social-walled garden, Mastodon is free, open-source and decentralized.

What does this mean? Anyone can run a Mastodon site, with whatever rules they like, and support it as they see fit: donations, subscriptions, ad or simply out of love. The majority of Mastodon communities are running on love.

There are Mastodon sites set up for geeks (Mastodon.technology), artists (Mastodon.art), academics (Scholar.social), gamers (Elekk.xyz) and dozens of other interests. And while you could sign up on one and interact with others who share a passion or interest, Mastodon is federated, meaning you also can easily follow people on other servers.

Think of it like email, which is similarly federated. You might use Gmail or an account provided by your employer. But you can still trade emails with people on Yahoo Mail or Hotmail. I might like tooting with other punk Libertarians on Sunbeam.city, but I can still follow a bunch of cat lovers on Toot.cat.

And one upside of this sprawling network is that you’ll probably be able to snag your preferred handle on at least one of them. No more @ryan96789!

Do Mastodon’s principles mean that angry racists could set up a server, too? Sure. But operators of other servers aren’t required to federate with communities they don’t like. Trump fans are flocking to Mobile.co, but they’re largely stuck talking amongst themselves.

The known universe of Mastodon servers is small but growing, and its userbase recently surpassed 2 million. (It’s especially big in Japan.) Because it’s open source, people are able to build sites with unique features, and there are many mobile apps for iOS and Android that can provide a familiar interface for scrolling and posting. To learn more, visit joinmastodon.org.

Mastodon is just one suburb of the open and federated social web (dubbed ‘the fediverse’). There’s also Pleroma, Friendica (like Facebook), Peertube (like YouTube) and Pixelfed (like Instagram). And while individual instances of each may not survive, there are new places to explore popping up every day.

Ryan Ozawa is the communications director for local tech company Hawaii Information Service, and a lifelong technologist. You can follow him on Twitter at @hawaii, or on Mastodon at hawaii@mastodon.