Calendly - Scheduling appointments and meetings is super easy with Calendly.
CoreUM - The Ultimate Meeting Application
Crewdle - secure and green made simple
Etherpad Lite
Meetin.gs - Free, Easy and Better Online Meeting Organizer
MOMO BOARD - Free Community App, Group App, Chat, Cloud Storage
Mural.ly - Google Docs for Visual People
Weet is an asynchronous video communication for remote teams
World Time Buddy - Ridiculously easy world time and meetings across time zones!