Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.

Pastimes - Find friends who do your favorite activities

Eventbrite - Discover Great Events or Create Your Own & Sell Tickets

Stop The Bullshit - Hide posts & block sites that publish fake news on Facebook

Bigtent - BigTent is a web-based organization and communication portal for groups.

Securing Democracy - A "disinformation dashboard" tracking Russian propaganda