What are some alternatives?
HyperOffice - HyperOffice: Pioneering online collaboration software since 1998. Share documents, manage tasks, email, intranet, sync Outlook, mobility. Free trial.
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!