Refer-A-Friend scripts (also called "Tell-A-Friend",
"Recommend", etc) ordinarily allow you to enter a number
of email addresses along with a message. It typically
asks for your name and email, and then sends your
message to the addresses you specified. Included is
a link back to the site inviting the recipients to take
a look.
Like with anything, these types of scripts have their
pros and cons. For instance, it's a great way to let
other people promote your site for you (don't
underestimate the power of referral!). On the other
hand, the form could be abused: someone might choose
to send messages to people he dislikes, or he may
send vulgar or obscene emails to random addresses,
etc.
I've used these types of scripts on two of my domains.
On one of them, I eventually removed it due to repeated
abuse. On the other domain, I've never had a problem in
the 18 months that the script has been in use.
Lots of places offer Refer-A-Friend scripts for free.
For instance, check out:
- BigNoseBird (a wonderful and helpful website)
- Master Recommend (a 'pro' version is also available)