MimerDesk is a Web-based groupware environment designed for a wide variety of uses such as personal management, computer-supported collaborative learning, carrying out projects, and setting up communities.
How about these features (kind of like Facebook): o read messages online if they prefer not getting Email o post messages to the group from the web Email tool o personal TODO list, calendar, address book, files, friends o group email, files, links, address book, reviews, calendar, news, voting, projects, and forums (chat is not working for now) o Easy visibility of all group members, with only the details YOU want to share with others visible.