UPDATE: Subscriber’s Magnet is no longer available. Try ClickFunnels instead.My Thoughts On Subscriber’s Magnet
Subscriber’s Magnet is the WordPress plugin I use to easily add opt-in forms to my sites. The opt-in forms themselves still need to be created using an autoresponder service like Aweber or GetResponse. But the plugin makes it easy to add your opt-in form to posts, your sidebar, as a drop-in window and as a semi-transparent bar on your site.