I’ve got something I call vcalxical.pl, which is a perl script that logs into an Exchange server running IMAP, and then reads a mailbox that is really a calendar, and pulls out the VCALENDAR parts, and formats them into an ics-type file. You can import this into Apple’s iCal or into Sunbird.
Now, it’s far from perfect, but it works for me. Your Windows guys would have to have IMAP enabled, and I’m guessing it doesn’t take much to break things if they really want to. (For instance, at some point in time things changed from plain text to HTML, who knows!?)
The idea is this, when stuff gets scheduled in Outlook/Exchange (which you don’t use cuz you don’t use Windows) it’ll show up in iCal or Sunbird after the script runs via a cron job. Theory, anyway… I think it would be better to have the calendar on available via webdav, as I don’t know how the apps like having the file changed on disk willy-nilly. That way it really is a remote calendar.
I’ve been using it on and off, but not testing it too heavily. iCal seems to be popping up alarms to stuff. Sunbird, I’m not sure yet…
Still, we hack on…