Newsletter Co-Registration, and other Partnerships
http://www.excessvoice.com/article105.htm

Usborne, Nick
Excess Voice
2006

Abstract:

When someone signs up for my newsletter, I list some other newsletters they might be interested in on my site's thank-you page. People can simply check a box next to the other newsletters they want to receive, click one button, and they're done. The publishers I partner with do the same for me, listing the Excess Voice newsletter on their sign-up thank-you pages.