I came across [tag]Zookoda[/tag] about a week ago. The name was a little odd, and I wasn´t really sure what it actually was. But I had to visit their site and see for myself. It turned out that their system is awesome and free, a great combination.
If you have a blog, you should really consider to try Zookoda. It´s a [tag]newsletter[/tag] service, where you can put a form on your site, where your visitors can put their e-mail to subscribe to your posts via e-mail. You decide when they should get the newsletter and how many new posts should be in it.
This is a way for your readers not having to visit your site every time you post or every day, they can just wait for your newsletter to arrive in their inbox.
So far this service has been great. Their newsletter templates are also great looking.
Give it a try today at http://www.zookoda.com