[Shawn's Thoughts] Several folks have been asking about Google Calendar and Windows Calendar, and how to link them together.  They’re both using the icalendar format to store their calendar entries, so subscribing to a Google calendar should be pretty straight-forward.  It is, once you know how to find the correct URL.  In this exercise, you’ll be sharing out your Google calendar, and subscribing to it inside Windows Calendar.

Shawn has a great post describing how to subscribe to a Google Calendar from within Windows Calendar. I have also used the same technique to subscribe to an iCal calendar from .Mac since they all use iCalendar as their file format.