torvad,
I came here just now in an effort to find out about the exact same thing. I haven’t yet found one that I know how to use to make it actually work on my blog. For example, I found a plugin that added a basic registration widget (email only) with post notification. But, it hasn’t been sending out the post notifications. No doubt I am overlooking something simple.
At any rate, it is called Post Notification. Maybe you can get it to work?
~Cara~
