Note: Most organization failures are caused by people using inappropriate systems, so take a moment to decide which scheduling system will best fit your needs.
There are plenty of internet calendars out there -- far too many to review -- but the most popular one is Google Calendar, or gcal, available at www.google.com/calendar. Gcal is based on software calendars such as Outlook, but the data are stored online so that you can access your calendar from anything that has internet access: your laptop at the library, your home computer AND your office computer, or your iphone.
Google Calendar (Gcal) Summary
Price Free; must sign up for a free Google Account
Recurring Events Extremely Flexible: every n days, every n weeks, specific days every n weeks, every n months (by date or day), or every n years
Pre-event alert Very flexible: 0 - 99 minutes, hours, days, or weeks in advance
Available views Day (detailed schedule), Week (detailed schedule), Month (list of events on this day), Custom
Syncs with Has funtionality to sync with Outlook, ical, Windows Mobile, iphone, or Blackberry. However it "syncs" best with something running Android OS, since it doesn't have to actually sync at all.
Task List A rudimentary task list is included, and is improving continually; online task lists such as Remember The Milk try to be compatible with Gcal also.
Other Offers options for multiple calendars (work/personal, or Mom/Dad/Daughter/Son, or whatever) and allows you to adjust privacy settings to determine who can view how much of your calendar.
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