No sign-up fees. We have an unlimited supply. This is a subject of much discussion. Some people have some strange definitions. When they send you their response - that IS NOT spam.
Someone comes along and collects e-mail address from the newsgroup.
That IS spam. You send a request to someone to send you information in an e-mail. They send you this information, and maybe a follow-up or two. This IS NOT spam. These same people continue to send you information months after your request.