The type of viral marketing that we are talking about would pass from a person to friends/family -- we would be asking that people interested in the case spread the e-mail to their friends/family and those people do the same. So, very little would get filtered out because you are set up to receive e-mails from friends/family.
Spam companies buy address lists and send out mass e-mails -- you set up filters to pull out mail that comes from known spam sources or mail that doesn't come from sources you approve. We don't want spam.
Think of it as being passionate and having enough time to write to each of your friends to tell them this interesting case you are working on. That is what this e-mail would do except that we would write the message 1 time rather than over and over. If people choose to pass it on -- great. If they choose not to pass it on that is fine also. But, we will have given them the opportunity.
I think we can play on the idea of 6 degrees of separation and increase awareness and never come close to spam.
Because it is going from person to person and not asking for anything but consideration I don't believe we are at risk for any laws.
Thank you for this good explanation. I'll leave this avenue up to you and Doogie. It sounds worthwhile.