] This (imaginary) company has a simple business model. It
] operates a really big password-protected SMTP relay. It
] sends email from anybody to anybody for 1¢ ($0.01) each.
] You open an account with them, drop in say $10 and
] you've bought the rights to send 1,000 emails. Or you
] could set up a monthly billing with your credit card, or
] whatever. You can't send more than 100 emails in a day
] without an (email) exchange to verify that everything's
] all right.
]
] Every email that it sends it signs digitally. Then, you
] set up your email client to send all email that hasn't
] been signed by SMTP4All or one of its competitors (there
] couldn't be more than a couple of hundred) to the junk
] folder. Then you tell your friends to go and sign up with
] one of these guys if they want you to get their mail.

Comments? I don't like his answer for mailing lists... Need to rethink that part a little bit...