jaromy

<h4>Sign Me Up</h4>
This plugin is a widget that adds a simple sign-up form to your WordPress site, allowing visitors to subscribe to your mailing list. It serves as a front end to <a href="http://www.phplist.com" rel="nofollow ugc">phpList</a>, the most popular open-source newsletter manager (over 1.5 million downloads according to their website). The widget connects to phpList via AJAX, which allows a visitor to subscribe without leaving your WordPress page – no refresh or redirect is necessary.
Features:
<ul>
<li>Add a simple “sign-up to our newsletter” form to your WordPress site</li>
<li>Provides a back-end connection to the powerful open-source mailing list manager, phpList </li>
<li>Maintains the consistent look, feel, and branding of your WordPress site</li>
<li>Uses AJAX – no page refresh or redirects. Status & feedback are displayed on the same page as the form</li>
<li>Minimal, elegant, simple. Seamlessly blends in with your theme by incorporating existing styling rules</li>
<li>Easy customization – change the text of each form element so it says exactly what you want</li>
<li>Widgetized – easily add it to your site via drag & drop</li>
<li>Error checking – client side validation via popular jQuery Validation library provides immediate feedback to the user and reduces erroneous data</li>
</ul>
More information
<ul>
<li><a href="http://www.jaromy.net/wordpress-plugins/sign-me-up/" rel="nofollow ugc">Sign Me Up</a></li>
</ul>

Sign Me Up

Add a simple straightforward sign-up form to your WordPress site. Integrates with phpList, the most popular open-source newsletter manager.

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This plugin imports forms from you PhpList host into wordpress. 
Your subscription forms can be used anywhere in wordpress using shortcodes. 
Custom user attributes defined in phplist are also taken into account. 
The plugin uses async calls (ajax) for registrations. You can fully customize the respone on success or failures.
NOTE: This plugin will only work with self hosted PhpList environments. It does not work with phplist.com accounts.
<a href="http://coderisk.com/wp/plugin/phpls/RIPS-6cAWMzmXxg" rel="nofollow ugc"></a>

PhpList Subber

Integrate your PhpList subscription forms in Wordpress, including user attributes in phpList.

Sign Me Up vs PhpList Subber