split63:
Any example sites so I can get a sense for how this will appear to customers? I have FEC to complicate things.
At what point does it send the emails and is there any sort of email validation?
Can you control the number of emails requested and the message displayed?
For example, "Enter 4 emails to get $2 off your shipping"
I would imagine this will get a lot of bogus email addresses but it does have good potential.
What would probably be better is if it sent emails and if and when the emailees came to the site, only then did it retro give the discount. For example, if 4 emails gives a $2 discount, then for each emailee, $0.50 would be refunded. Timing of refunds would likely be an issue.
Perhaps after 1 week, it expires, and refunds the accumulated amount, if any.
I have it set up on one site http://store.flavorwood.org
As for the options, you have set shipping charge, set handling fee, free if total is less than, free if total is greater than, free if weight is less than, free if weight is greater than, free if item count is less than, free if item count is greater than, captcha yes/no, and # of email addresses required.
The module does a good job logging the email addresses used in the DB to prevent them from being reused.