Backchannel Chat - Backchannel Chat is best in class discussion tool that is intended for teachers to streamline their class activities.
Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
NowComment - NowComment is a complete suite of collaboration tools, streamlining group discussion, annotation, and curation of texts, images, and videos.
Event Hunt - Startups and Tech Events Curated By Locals
Eduflow - Digital learning that actually teaches students something
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets