The plans for this list were pretty straightforward:

• new product info
• troubleshooting tips
• industry news (when this particular company has an insight not already written up by others)
• pointers to the company Web site

1. Membership open to anyone -- not just customers or investors. There are a couple of risks in this membership:
   • competitors could use the list to obtain a market advantage, or could surreptitiously take the e-mail addresses for their own mailings
   • critics could use the list to, well, criticize the company
   If you are concerned about these risks in your own use of a customer mailing list, then make sure the e-mail addresses can't be accessed by outsiders, and have the list moderated (or better yet, send a digest or "e-letter").
2. Send a consistent content length, as opposed to sending messages at regular intervals. In the event that list members forget the list exists because the company has so little to say, it's time to shut the list down.
3. Send only ASCII text, as opposed to embedded images or HTML. Even if most mail readers support HTML content, commercial e-mails are best aimed at the least common denominator of technology. Likewise, messages won't include special characters or depend on word wrap to control line length.
4. Take advantage of ListBot features such as a demographic database of subscribers (though collecting those demographics may discourage some from subscribing) and an archive of previous messages (in case new subscribers want them).
5. Invite customers via direct e-mail to join the list by direct e-mail, as well as via a passive invitation on the Web site. Direct e-mail is only sent to addresses the company already has on file (e.g. customers, potential investors, etc.). It's still half-unsolicited e-mail, but not quite spam, especially if it's clearly marked as a one-time message.
6. Keep addresses confidential except with permission from the subscriber. Some lists sell their addresses, ensuring more commercial e-mail sent to their customers. If a company does this, it's important to let the subscribers know, and to make sure the addresses are only placed in the hands of relevant interests.