Confluence - Confluence is content collaboration software that changes how modern teams work
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!
MS SharePoint - Share, organize, and discover information with Microsoft SharePoint. Learn about SharePoint Online, OneDrive for Business, and Apps for SharePoint
LinkedIn Premium - LinkedIn is a social network helping brands and professionals to connect, identify sales prospects, hire talent, and promote their business.
Notion - All-in-one workspace. One tool for your whole team. Write, plan, and get organized.
Salesforce Chatter - Salesforce Chatter provides a suite of collaboration features to any application built on Force.com.