A form of pyramid scheme. A person subscribes to service, lure a few
unwitting victims to subscribe under his name and get the free stuff.
The few new subscribed must get more referals to get freebies for
themselves as well. It keeps going on.
Plus when you sign up, your email address gets plastered to bazillion
spammer list and there's no stopping a flood of new spams.
Old caveat emptor: if it's too good to be true, it probably is.
