Unlike some (more famous) email referral systems, the user
doesn't need to leave your site to make the recommendation,
it's all done right there on your own site.
The 'Thank You' page prompts the user for six more referrals,
and it keeps coming back for more (unless you choose otherwise
- see advanced features)!
The referral message is written by you, not the sender
(unless you choose otherwise).
The advantages are: a) less effort for the user, so they
can concentrate on writing names and addresses and b) your
text sells the site more strongly than a message written by
the sender.
The referral message is so highly personalised that the recipient
cannot possibly mistake it for spam. They WILL read it.
You get lists of all the names and addresses (if you want) so you
can follow up, although I would advise against it. The recipient
has already been given a glowing report of your site by their own
friend, so a further message from you will only spoil it. Why not
just relax and watch the referrals pour in?