Mobilizon is a free open federated events system for the Fediverse, designed to get people off Facebook Events. You can follow the project here:
It's currently in beta testing, and is made by @Framasoft (the makers of PeerTube and many other free open projects).
Mobilizon's official site is at https://joinmobilizon.org/en/
This is a brand new server run by the main developers of the project as a spin-off of mastodon.social It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!