Slack - A messaging app for teams who see through the Earth!
HeySpace - HeySpace is the only free task and simple project management software with communication and collaboration feature.
MS SharePoint - Share, organize, and discover information with Microsoft SharePoint. Learn about SharePoint Online, OneDrive for Business, and Apps for SharePoint
Rivers IM - Simple, fast & secure team collaboration platform
Jostle - A new kind of employee intranet that drives engagement & workplace culture. Achieves social participation in work relevant way. Participation rates are over 85%.
Workplace by Facebook - Connect everyone in your company and turn ideas into action.