I just stumbled across the below service. It’s new and still in beta, but looks promising. Check it out.
RSSCalendar
RSSCalendar is an exciting new way for individuals and organizations to share their calendars with family, friends, and co-workers – utilizing the latest in “Really Simple Syndication” (RSS) technology, including RSS channel creation and aggregation. Not only is RSSCalendar easy to use but it is also easy to administer, and setup is a snap.