If you follow any internet marketing guru, then it's very apparent that they regard e-mail list marketing as crucial to success. And they use services such as Aweber, Get Response etc. The cost of these services is often more than shared hosting at $20 or so a month.
The idea is that you build a list of subscribers, and e-mail them details about offers on a regular basis.
To ensure e-mail deliverability, these services aim to white-list their e-mails with the various ISPs so that the spam filters let the e-mails through.
If you send emails from your web-hosting server, then you risk getting your site shut down after just one spam complaint, (and you get severely limited on sending frequency) so it seems like you may have to use the specialist e-mail marketing services to avoid this problem.
If you send via BCC on say Gmail, then it's kind of like firing a machine gun.
Then, we can use computer software to send e-mail at a steady pace, but how do we handle the opt-in?