Say you wanted to do calendaring on campus and between campuses of a multicampus university. Suppose that each of these organizations had their own technology stacks and standards. How would you do it?

At the simplest level, just saying "everyone publish all relevant campus calendars in the iCalendar format" would allow anyone with an iCalendar compatible browser to subscribe to the calendars. Of course, by publish, I mean "make available via an HTTP GET." As a Mac user, I can see immediate value in this. What about Outlook users? Does Outlook have the ability to subscribe to iCalendar formated calendars delivered via HTTP?

Going beyond just one way communication of calendaring, what else would you do? Are there open standards for creating calendars for meetings? How are they supported? I'm curious how hard it would be, for example, to allow individual instructors to create course calendars in an open system. I've been doing this for sometime using iCal (on the Mac) and a php iCalendar reader.

I'd like your help putting together a resources I could share with a group of CIOs and IT managers on this problem. I've created a page on my Wiki and if you've got an idea, a standard, a case study, or a question, please feel free to leave it there.