I have previously sold Small Business Server to several dozen of my clients. In order to remotely manage their systems, I am forced to use either IE's RDP plug-in or Remote Web Workplace (a Microsoft-created web site on these servers that uses RDP) if I cannot get in via VPN.

And, as I mentioned, my whole email storage system currently lives in Exchange 2007 as a quite intricate set of private and public folders, not addressable by IMAP.