Livetiles - Intranet solution for small to large businesses
Workplace by Facebook - Connect everyone in your company and turn ideas into action.
Communifire - Enterprise Social Collaboration Software
Salesforce Chatter - Salesforce Chatter provides a suite of collaboration features to any application built on Force.com.
Oak Engage - Oak Engage is a digital workplace for enterprises that need to communicate with their workforce. Connect your teams. Engage your people.
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!