BORG is a calendar and task tracking system written in Java. The calendar provides a nice month view, month-print, email reminders, popup reminders and to do list. The task tracker tracks issues through various states.
Microsoft Exchange compatible server and client libraries
OpenChange is a portable Open Source implementation of Microsoft Exchange server and Exchange protocols. It provides a complete solution to interoperate with Microsoft Outlook clients or Microsoft Exchange servers. OpenChange client-side library is used in existing messaging clients and is the solution in new projects to communicate natively with Microsoft Exchange and Exchange-compatible servers. OpenChange server is a transparent Microsoft Exchange server replacement using native Exchange protocols and does not require any plugin installation in Outlook.
EGroupware has moved to Github, please find all our downloads there: https://github.com/EGroupware/egroupware/releases EGroupware is a multi-user, web-based groupware suite. Currently available modules include: email, addressbook, calendar, infolog (notes, to-do's, phone calls), content management, wiki, project management, tracker, timesheet, knowledge base, CalDAV/CardDAV
It's professional Extensions modules for Egroupware : Issue, decision and risk mgmt,Meeting Agenda/Report,Project Capitalisation PDF for every egw modules, objective mgmt, project team and calendar, dashboard, ISO 15504 SPICE Process Description
Yank is a simple notekeer and todo-list manager using the gnome and gtk libraries. It feels stable and usable enough to be released to the public but it surely lacks some (not so important) features which might be added later.