I have recently been given a similar task, the desire to share calendars/schedules between the Kentucky office, Australia and the world travelers. At first I put it to the back burner, thinking it would take more development time that allowed but some random link mentioned Mozilla Calendar
Standards Based Calendar Client Project.
All by it’s lonesome, not a big deal, but checking out iCalShare lead to,
PHP iCalendar is a php-based iCal file parser. Its based on v2.0 of the IETF spec. It displays iCal files in a nice logical, clean manner with day, week, month, and year navigation, printer view, RSS-enabled, and searchable. It supports 12 languages, is fully theme-able, and has complete timezone support.
Which combined with, How can I share my calendars?
To share your calendars, you need access to a webDAV server. If you run your own web server, you can install mod_dav, a free Apache module that will turn your web server into a webDAV server. Instructions on how to set it up are on their website. Once you set up your webDAV server, you can publish your calendar to the site, then subscribe to it from any other Mozilla Calendar. Automatically updating the calendar will give you a poor man’s calendar server.
And maybe a very nice solution. I still have to play around with WebDAV on IIS, but this might be a workable combination. Oh, the delicious side effect might be to get everyong off of Internet Explorer, Outlook and Outlook Express.