Workplace by Facebook - Connect everyone in your company and turn ideas into action.
Slack - A messaging app for teams who see through the Earth!
Salesforce Chatter - Salesforce Chatter provides a suite of collaboration features to any application built on Force.com.
MS SharePoint - Share, organize, and discover information with Microsoft SharePoint. Learn about SharePoint Online, OneDrive for Business, and Apps for SharePoint
Bitrix24 - Bitrix24 is a free (for small businesses) social enterprise platform. It is a united work space which handles the many aspects of daily operations and tasks. Create your own social intranet in minutes!
Jostle - A new kind of employee intranet that drives engagement & workplace culture. Achieves social participation in work relevant way. Participation rates are over 85%.