"The server is going down for maintanance": how do YOU tell your users that?

[ArcaneMagus]

Yea I'm rather lucky in that I only have ~30 people on my server... and none of them are up at 1am when I take the server down for maintenance

[Mistoffeles]

Suggestion:

If you are going for a 40k user installation, I bet Zimbra (the company) would help you write a Zimlet that you could enable by default which would allow you to post notices that would update immediately in the Zimbra (AJAX) web interface. If you made it all bold and flashy it would get users' attention fairly readily. You could also have the Zimlet trigger a pop-up. If so, I recommend including a checkbox for them to click that cannot be tabbed to and does not have a hotkey associated with it, to prevent users from accidentally sending it away due to having been typing when the pop-up popped up. I can't tell you how many times I have been hit by that and ended up doing something I Really Did Not Want To Do{tm}.