Sorry, but unless I can manage my email with sensible rules, I'm not going to manage it.

I need to be able to have rules that let me move email automatically after it's been read or after it's been in the Inbox for some time. But that's not really possible with most server side rules engines (they only look at mail when it arrives), client side rules engines are dead and I don't use email from a fixed desktop machine anyway, and I'm not going to write an imap based filtering engine (I did it once on company equipment, and it wasn't fun enough to do it again).

So Inbox 40,000 it is.