There are federated microblogs (GNU Social), social networks (Diaspora), wikis (http://t.co/V9evCj0WD8) but no auth services yet AFAIK.
miniblog.
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Replacing npm (the tool and the organisation) with a federated alternative by npm inc's former CTO! https://www.theregister.co.uk/2019/06/04/npm_cj_silverio_javascript/
(I had no idea that so many registries were sprouting!)
Perhaps it would be useful for Mastodon instances to provide their own preconfigured clients.
Federated tooting has several similarities to email, but when I send email on my phone, I use the GMail or Yahoo apps. They're tailored and require less setting up.
When people talk about federated systems, they frequently compare with email. Email has been successfully distributed, but I think it's an outlier. It's rare, especially today, for popular tech to be distributed with multiple implementations.