Not your website — the page you point a campaign at. One page per launch, event, offer or list, so you can see which one actually worked.
Prove demand before you build, and leave with a list of people to tell when you ship.
Turn a reader who liked one thing you wrote into someone who hears from you every week.
Convert someone who just heard the event exists into someone who has registered for it.
Not sure whether you need one of these or a website? Compare the tools — several of them are website builders, and we say so.