[Discover] Groupware Bad http://www.jwz.org/doc/groupware.html
(business design groupware programming) 
[Discover] Redmine http://www.redmine.org/ (project rails opensource ruby)
[Discover] The Groupware Server for Web 2.0 - Citadel.org http://www.citadel.org/doku.php (email collaboration linux calendar)
[Discover] Main Page - Bongo http://www.bongo-project.org/Main_Page (email server calendar collaboration)
[Discover] CalDAV - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/CalDAV (calendar wikipedia standard specification)
[Discover] Redmine http://www.redmine.org/ (project rails opensource ruby)
[Discover] The Groupware Server for Web 2.0 - Citadel.org http://www.citadel.org/doku.php (email collaboration linux calendar)
[Discover] Main Page - Bongo http://www.bongo-project.org/Main_Page (email server calendar collaboration)
[Discover] CalDAV - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/CalDAV (calendar wikipedia standard specification)