ccNewsletter is a Joomla! 1.5 Native Open Source newsletter component. It is the easiest way to send newsletters to your users, fans or clients in Joomla! 1.5. You can be sending newsletters in just under 10 minutes from now!
ccNewsletter is an extension with one newsletter list, which can be sent to one group of subscribers. Its simple, yes, and also very easy to use.
* Joomla! 1.5 User synchronization