Check it out:
This is a very polished new tool, that enabled you to create schedules for agents and groups to go into maintenance mode.
It is essentially a web service, with a VERY simple UI, to allow users to create schedules for maintenance mode, or for on-demand maintenance mode. It even includes a nice tool/icon to place on all your servers desktops, to allow server admins to immediately place a server into maintenance mode from the server itself (which communicates with the central web service).
On top of that, it includes a Windows 8 app as well as a front end to the web service.
Very, very nice!