We actually have most of the technology for this in place since we intended to implement and publish it. But we are unsure of the licensing of the Notifier-mails, therefore we haven't encouraged it.
What does exist is that a user can "checkout" an email address at Project-GC where the site will listen for notifier mails, and forward the mails to that address. What we do not have, is a system to keep track of whom is covering which areas and what types of emails and for which cache types.
Well, we actually have parts of the tracking system too, but it's hard to make it work in a way where we could know if someone stops forwarding. For example, we can not expect there to be a new Multi-cache ever week in the most northern Norway. Therefore we can't keep track that the notify-suppliers are still active.