Zohovirtualoffice
http://www.zoho.com/virtual-office/
Zoho Virtual Office is a groupware that provides a virtual collaboration platform using which individuals and groups can communicate, collaborate, organize and share information seamlessly using number of useful applications like E-mail Client, Virtual storage for Documents, Personal and Group Calendar, Task Scheduler, Contacts Manager, Instant Messaging, Discussions board, etc. Zoho Virtual Office allows users to create multiple groups, and use all of these components within groups unleashing the real power of collaboration. This helps you increase the efficiency and overall effectiveness of your business.