Active Desktop Calendar!

Microsoft Outlook, part of the Microsoft Office Suite (not to be confused with Microsoft Outlook Express), is a personal information manager that lets you manage your e-mail, calendar, contacts, and tasks.

Rainlendar is a feature rich calendar application that is easy to use and doesn't take much space on your desktop. The application is platform independent so you can run it on all major operating systems: Windows, Linux and Mac OS X. The appearance can be customized with skins and you can even mix different skins together. It is possible to use Rainlendar with other calendar applications too. Rainlendar uses the standard iCalendar format to store its events and tasks so you can easily transfer them between applications. You can also subscribe to online calendars including the Google Calendar and edit your Outlook appointments directly in Rainlendar*. »

An offline calendar without any other calendar integration. You can easily create recurring events and setup reminders, it can also display week numbers.

CalenGoo gives you a fast and easy way to access and change your Google Calendar (or Google Apps Calendar) with your Android device. It can either work with the built-in calendar or it can sync directly with Google.

This program helps you organizing your dates and tasks and reminds you of upcoming events.

BORG is a combination calendar and task tracking system. The calendar supports all sorts of appointments and also a simple todo list. The calendar functionality is similar to that of other PIMs, such as Microsoft Outlook, Mozilla Calendar, Palm Desktop, Yahoo Calendar, etc... The Task Tracker goes way beyond todo's and might better be called a project tracking system.

BEAUTIFULLY DESIGNEDDigiCal’s diary planner and organizer provides a clear and beautiful overview for your events and appointments.• Conveniently switch between 7 calendar views (day, week, week agenda, month calendar, text month, year and list view in portrait and landscape mode).• The slick dark theme allows for better visibility in low-light settings and night mode.• Event keyword image matching available in all 27 languages!• 6 highly customizable widgets with different theme styles and views: (FREE: list, day, day list, day grid widgets; PREMIUM: 2 extra widgets –text month and month calendar widget)• Intuitive navigation between days, weeks and months with zoomable day and week view. »

DeskTask connects to Microsoft Outlook and displays your calendar and task items on the desktop. * Your tasks will always be visible, saving precious time to launch or switch to Outlook. * Just minimize every window, and see what are the items due for today or tomorrow. * DeskTask displays the whole week so you can be prepared to organize your work. * Besides the calendar items, the Outlook to-do list (Folder Tasks) is also displayed. If you work with Outlook, DeskTask is for you

MemoCalendar.net is a light-weight and easy-to-use online calendar like a usual memo calendar on the wall. Behind every day a small note can be deposited. MemoCalendar.net is free and without registration (login) usable.

GMinder is a reminder program that waits in your system tray and alerts you when you have an upcoming Google Calendar event.

30 Boxes is an online calendering tool.