I'm working on an Intranet for the Archdiocese, and one of the primary concerns brought up by the Data Center is online calendaring. They mentioned that our offices already use Microsoft Exchange/Outlook for shared and personal calendaring functionality, and they don't want to create duplication of efforts (or, worse, mismatched data) between the Intranet and Exchange.

My searching so far has been entirely futile, but I'm wondering—is there any way at all to import, export, sync, or do pretty much anything with calendar data in MS Exchange? Using Drupal, I can grab almost any type of information from anywhere and output that data in any format imaginable, so it's hard for me to believe a product as huge as Exchange could be entirely insular.

(This is related to my earlier question about whether I should work with SharePoint for an Intranet). Also, here's the reference issue on the Archdiocesan development site: Decide what to do about Online Calendaring...