Whether you use calendars in your Apple products or Microsoft Products or web based systems like Google or Yahoo, the connecting thread is the .ics file. You import/export calendar information using the .ics files.
Traditionally you paid for the software that permitted you to create .ics files. Programs like MS Outlook or iOS. If you didn’t pay for the software, you had to pay for the connectivity to generate an .ics file from a web based calendar service.
I discovered, just today, that Sunbird 1.0 beta1, a standalone free calendar program by Mozilla foundation now lets you work offline and create .ics files. I just want to put in the good word. Does Sunbird handle time zone differences and daylight savings well? Well, I don’t know for sure but I think we have program that fills a sweet spot.