Google Groups - Google Groups allows you to create and participate in online forums and email-based groups with a rich experience for community conversations.
ifttt - IFTTT puts the internet to work for you. Create simple connections between the products you use every day.
DownToMeet - DownToMeet is a platform to organize, find, and attend group events.
Zapier - Connect the apps you use everyday to automate your work and be more productive. 1000+ apps and easy integrations - get started in minutes.
Mighty Networks - Mighty Networks enables entrepreneurs, organizations, and companies to create and grow a community-powered brand.
n8n.io - Free and open fair-code licensed node based Workflow Automation Tool. Easily automate tasks across different services.