> Yep, but you wouldn't need a leased line for domain names?
> The ISP could just bang everything in a mailbox for *@company.com
> and the LAN mailserver could pick it up whenever.

On the subject of rants and mail delivery mechanisms:

There are many ways of doing internet mail delivery.  Most of them involve
greater or lesser degrees of brain damage, and this one is no exception.

The problem is that there is information passed along in SMTP sessions which
isn't included in the bodies of these messages.  This information is vital
in order to ensure that the mail is delivered to the correct recipient.  If
you throw this information away by dumping all the mail (i.e. the message
bodies and headers, but no the SMTP envelope stuff) for a domain into a
single corporate POP mailbox, then you're losing information about who the
intended recipient was.  This is damaged and wrong and lends itself to
unreliability.

If you have a permanent connection to the Internet, then the Correct Way
(where "Correct Way" == most reliable) to get your email is to use SMTP.  If
you have a dialup connection, then the Correct Way to get your mail is to
use a purpose-built store-n-forward system, of which UUCP is still the best,
despite the efforts of almost all software vendors in ignoring this basic
fact (and tailoring their individual products to square the circle). 

(As you can tell, this is a subject which really gets up my nose, mainly
because of the amount of grief and administrative work it causes me.  Maybe
I need a cold shower.)

Nick