> Tis is not what I'm writing about about above.  I'm writing about
> having no alias file at all, about there not being a file anywhere
> on the system that lists the mail aliased for the various lists,
> about there being no file that encludes lines like the following:

> ie, with this system you can do the following:
> 
>   # newlist listname
> 
> and then immediately have the list live and supported under your MTA
> without editing a single file or pasting or piping the aliases into
> anything.

This is still possible with sendmail.  It would involve a 
script and the user class of sendmail's K command, but is doable.

   # nospam is the account/alias name; must NOT include a FQDN!
   Kuser user -m -a<>
   DLlocal:nospam

What this does is forward all unknown addresses that *should* deliver on
the current system to a given account or alias.  This account or alias
would call a script, which in turn would check to see if it is indeed
a list (check for its existence in $prefix/lists?) and if so, execute
the appropriate commands.  If not, send back a bounce, or send to the
next test.

I personally prefer to call procmail first, as it tends to be more
extensible for multiple situations like this.

Chris