Ooh, check this one out: https://pinafore.social/. It's a progressive web app for Mastodon, insanely fast and responsive. Performance out of this world 👌
Interface is a bit birdsite-like, which seems a bit less cluttered than the default Mastodon UI. I like!
Server run by the main developers of the project It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!