google-calendarGoogle Calendar is very user-friendly, and very good at helping you manage your days. If you already use another calendar, consider switching over. If you do not already use a calendar—start using GCal immediately—it is that good.

5 Reasons Why GCal Rocks

  1. You can invite people to events or allow them to view your entire calendar with the click of a button. You can also easily make certain events private.
  2. It syncs easily with most popular smartphones.
  3. Even if GCal is not on your phone, you can tell it to send you SMS reminders of events.
  4. The quick add feature lets you add events as easy as “lunch with Randall Ryder at noon on September 23, 2009.” GCal will interpret your language and add it to the right day and time.
  5. It is free.

HOW TO: Stay Organized With Google Calendar | Mashable