My wife and I share an e-mail address but I may have to set up a separate
address for her (which would be used infrequently) to satisfy the
requirements of a site we each want to register on.

If it can be avoided, I don't want to screw around with log-ons, passwords
and the like and would like to be passively notified of any mail to the new
address, by which I mean I don't want to have to go somewhere every day just
to find out that there's no mail.

Which leads to my question: can mail to two addresses be downloaded together
and share one set of local folders?