If you ask for it, I can set up an MX for XYZ.wattle.id.au
in the DNS, where XYZ is your surname (see the policy for more details).
(This assumes that XYZ.wattle.id.au is not already allocated.)

Other DNS record types are available for DNS experts who know
what they are and know how and why to use them.  For example,
it is also possible to delegate a whole domain to you (so that you
could use HOST.XYZ.wattle.id.au), but this is unnecessary for most
individuals.  If you think this is what you need, please first
consider how you will supply the two or more nameservers required
(see RFC 2182 for more details on selecting secondary nameservers).

To register for a name in wattle.id.au, you would fill out a form,
to provide me with some contact information (eg: phone number, fax
and/or postal address) which I will keep confidential (unless you
explicitly authorise otherwise).

The DNS MX entry for XYZ.wattle.id.au would initially be pointed to an
SMTP server of your choice.  If you later decide to change to use a
different SMTP server, then you would let hostmaster@wattle.id.au know,
and I (or my successor) would change your MX so that people could
still mail you at XYZ.wattle.id.au, but it would go to your new address.

Before the MX can be installed, the hostmaster should be given evidence
that the postmaster of the SMTP server agrees to accept mail for
XYZ.wattle.id.au, and that this server already knows what to do with
such mail (eg: XYZ.wattle.id.au is in class w for sendmail, or in
a uucp config file).

If this person is not you, the best way is probably to start by requesting
the postmaster of the SMTP server to configure that SMTP server to accept
mail for XYZ.wattle.id.au, and put it into your mailbox (or whatever you
want to do with it).

Once this is done, the next step is to forward the E-mail reply from
the postmaster saying that your name has been set up, to
hostmaster@wattle.id.au.

This means that you can have an E-mail address like David@Keegel.wattle.id.au.
In my case the machine which is setup in the wattle.id.au DNS as
the primary MX for keegel.wattle.id.au (my personal domain) can
recognise the address david@keegel.wattle.id.au and rewrite it to
djk@cyber.com.au (my regular address).

The downside to this is that if you have an existing E-mail address, then
you have to change your E-mail address to XYZ.wattle.id.au.  Well, your
old address would still work of course, but if you write that on your
From: and Reply-To: then you haven't gained any benefit, have you?

Q: Does it cost any money?

No.  All you get is a DNS entry (and an entry in a confidential contact
database), and I am prepared to maintain that for free (as a service to
the Australian Internet), provided people will update me when they change
their info (including phone numbers etc).