Google Calendar Gadget in Gmail

Use the Google Calendar Gadget to put a mini calendar on your gmail page.  You can see your upcoming events while answering emails.  There are a lot of little gadgets you can add to your mail page, but the calendar gadget is really helpful.  Here is a tutorial for how to do that.

Special Interest Calendars for Google Calendar

Google Calendars provides a few special interest calendars that you can subscribe to with your account.  It places those events on your calendar, so you can be aware of what is going on.  I find these quite interesting and helpful.  I especially like that you can add holidays to your calendar without having to look them up.  Being a sports fan, I also like that I can subscribe to the schedules of my favorite teams.  I can turn them off and on, depending on when I want to see them.  Here is a tutorial video showing you how you can subscribe to some special interest calendars.