And my thoughts from day two of the course...
Exchange Control Panel
It's a sort of web admin light.
It's more oriented towards user and group admin, and could be handy. It also exposes itself via the user's settings in Outlook Web Access, so can be used to delegate control of groups to users.
On the one hand, I was doing this in Domino back in 2004 (with Domino 6.5), and I wasn't exactly pushing the boundaries... On the other hand, I can see why this would be very handy, and late is better than never.