Opensource Collaboration Solutions

Hula Project
(http://www.hula-project.org/Hula_Project)
Hula is a calendar and mail server whose goal is to be fun and easy to use, while scaling effortlessly from small groups to large organizations with thousands of members.


Zimbra™ Collaboration Suite Open Source Project
(http://www.zimbra.com/index.html)
Zimbra is an open source server and client technology for next-generation enterprise messaging and collaboration. Zimbra delivers innovation for both the administrator and the end-user as well as compatibility with existing infrastructure and applications (both open source and proprietary). Zimbra is open source in order to leverage the collective talent of the greater community, and to ensure investment protection for Zimbra partners and end-users., and to ensure investment protection for Zimbra partners and end-users.