I've been toying with an interesting idea at work, and since I couldn't come up with any ideas on my own (or my circle of friends/coworkers), I thought I'd present it here for more opinions (since courier is our current choice of mail server).

....

That much I think courier can handle (or so I've inferred from conversations on this list), and will most likely be what we do, but what I'm wondering is if anyone has heard of a way that the servers could be replicated (like a database does) so that people offsite could check their mail (IMAP) at the colo server instead of coming in via our slow DSL connection. So far, I've heard of several one-way options (eg. rsync or drbd), but nothing capable of passing changes both directions to keep both the colo and local servers completely in sync.

Though I doubt that this could actually be done, it does at least present an interesting concept idea, so I thought I'd put it up for discussion.