I think you should only spam non-forum members- you can easily get email address lists for quite cheap from certain places- you just need to have a script that compares it to the forum emails list so that my some chance members don't get spammed. I think spamming is a new and yet unexplored method of indoctrinating the masses into the world of stereo3d.
I hope your're joking. That would be a really bad idea.
Sending emails to people that did not give authorization would be sending spam. Spamming has bad reputation so you don't want it to get associated with stereo 3D. Also, if you send lots of emails using that kind of list, you risk getting your email server banned and it's almost impossible to get it unbanned so after that, you can't get legitimate emails through.