A flexible unified communications service for collaborative workgroups that can share files, import and export contacts and calendars from a wide variety of data sources and Web services, including Facebook, LinkedIn, Twitter and Google's Gmail. Entirely open-source based.
Price: Varies depending on market and number of user accounts
Requirements: Works on a wide variety of browsers and operating systems. We tested it in May 2013.
2033 Gateway Place
San Jose, CA 95110
408 500 0768 http://ox.io