Yahoo! 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.

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

Android calendar-app showing the weeks of the year (week numbers), 21 languages, syncable with Google Calendar: FEATURES* intuitive navigation with smooth transitions* day, week & month calendar* 48 colors per calendar, per-event color if supported by the calendar (Android Jelly Bean with Google Calendar only)* flexible recurrences (e.g., every 3 weeks)* birthdays & anniversaries with photos from your addressbook and editing* Fullscreen widgets* custom event font size* uses Android's native calendar backend and synchronization* no battery drain* moon phases and zodiac signs for birthdays* QR barcode sharing of events* NFC sharing (if supported by the device) NEW* free* no adsTRANSLATIONSnative language support for English, Arabic, Czech, Danish, Dutch, German, Greek, Spanish, Finnish, French, Hebrew, Italian, Japanese, Korean, Polish, Portuguese, Russian, Slovak, Swedish, Turkish and Chinese with more to come »

California is a new calendar application for GNOME 3. It's currently under heavy development.

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.

30 Boxes is an online calendering tool.

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. »

Keep track of all your Events with free SMS and Email notifications. Store and organize your Events and To-do on Ominder and never forget them again. Events include weather forecast for better planning.All Events and To-do include countdown and age timers for better management.

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.

KOrganizer is the calendar and scheduling component of Kontact, the integrated personal information manager from KDE.

CalendarWiz offers everything organizations need in one calendar. Do it all in one application with our shared calendar features, website plugins, room & facility scheduling, and mobile app. Ideal for education, churches, business, government, non-profits and clubs. Our mission is to provide a low cost online calendar service that is easy to install, customize and use. Free email support included with all plans.