Calendify - Calendify is an event community where you can share, publish, and subscribe to event calendars. It helps you to stay informed about what you are interested in and what is yet to come.
Google Groups - Google Groups allows you to create and participate in online forums and email-based groups with a rich experience for community conversations.
Upcoming.org - A simple way to share and discover interesting events
DownToMeet - DownToMeet is a platform to organize, find, and attend group events.
Morse - Create, shout out, and discover nearby events in real time
Mighty Networks - Mighty Networks enables entrepreneurs, organizations, and companies to create and grow a community-powered brand.