I just finished setting up Flarum at https://IdeaCow.org. It's a site I made for the student government at my university (our mascot is a cow) where students can submit ideas and others can vote and comment on them (inspired by software feature request sites). Right now we're still testing it which is why some of the posts might seem strange or random.
For a server we are using an AWS t2.small instance running Ubuntu 16, and will see how that goes (not expecting millions of visitors lol). Also Lets Encrypt, PHP 7.1, Apache. I struggled a bit at first getting everything working smoothly, and am happy to share advice on how I ended up getting things to work if anyone is using a similar setup and has trouble.
I was able to integrate it with my university's Shibboleth IdP using Auth0 and the mprove/flarum-ext-auth0 extension. I understand beta 8 may have support for different usernames and display names, which will be great if that feature does end up getting included, since I'd prefer to just show users' real names which we get from the SSO server.
Many thanks to everyone who's worked so hard on this amazing project! I'm really happy with how it turned out, and I know Flarum is only getting better.