I was talking with someone at lunch yesterday about this. Let's say you have a newsletter, as he does. It's packed with great information. Maybe you have two versions, a 4-page and an 8-page. The longer version tends to have quite small print.
You have a good list of email addressed from customers and prospects who have given you permission to send them information.
Now take that content and edit it down, break it up, make it shorter and the print bigger. Include illustrations or photographs wherever possible. Limit one main short article per email. Include a "share with your friends button."
If you have a long article, break it up in self-contained mini articles that can be part of a series. Use the series as multiple touch points over time - in marketing we call this kind of regularity lead nurturing. It is consistent and repeated exposure to your content. The other button you put in the html of the email is for feedback. Give them also a way to contact you and opt out every single time.
This is what we call the push format. Let's say you decided to also start a blog. In fact, you make the landing page of your URL the blog, with side links for your bios and the boilerplate of what the company does. When it makes sense, you include a media kit or press area - the lines between blogging announcements and wiring press releases is blurring.
In your blog you reference the newsletter and perhaps respond to comments and conversations you had with customers who contacted you about its content. You also use the blog to provide additional links to resources, outline specific issues or challenges your customers are facing (anonymous material is fine here, too) and tips from your experience.
Expand, deepen, simplify, explain, aggregate, enrich, enliven (your voice counts).
If you are in a highly regulated industry, you might need to figure out a way to provide feedback in a format that does not say it's specific advice. Include an RSS (Real Simple Syndication) feed and you have pull. Now your program integrates and provides value for both kinds of customers - those who prefer to hear from you directly, and those who are more the self-service kind.
You have not eliminated the personal touch. You have just enhanced your ability to do more face to face and have specific conversation about personal needs.
[make your own t-shirt at Reactee]