Kbin is also like Mastadon. It’s basically the same thing as lemmy, just with a slightly different user interface. (I personally like it better, which is why I’m here, lol.)

The main kbin instance, kbin.social, is hosted by a guy called @Ernest, who’s also the main (only?) dev who created kbin. But there are other kbin instances hosted by totally unaffiliated people, too.