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

TidyHQ - Organization management tool to support membership, subscriptions, event planning, and outreach.

DownToMeet - DownToMeet is a platform to organize, find, and attend group events.

Google Groups - Google Groups allows you to create and participate in online forums and email-based groups with a rich experience for community conversations.

Brüha - Brüha is your local entertainment and ticketing platform.

Membee - Membee is web-based membership management software.