Remi Corson

This plugin helps admins to easily create admin notification inside the WordPress administration.
You can choose many options and decide how and where to display the notifications.

Easy Admin Notification

Tested up to 3.3.1 Stable Tag: 1.4 Adds the ability to create easily notification in the admin panel

Eric McNiece

EMC2 Popup Disclaimer uses Fancybox (http://fancybox.net) to display the popup, and jQuery-cookie (https://github.com/carhartl/jquery-cookie) to detect user session. Creates a cookie named “emc2pdc” that can be viewed with regular developer tools.
Easy to use! By default the script is added to the wp_footer action and will work quietly. You can also force the display on pages via shortcode or function call: 
Shortcode: <code>[emc2pdc id="42"]</code> 
 -or- 
Function: <code><?php emc2pdc_force( $atts=array(), $force=NULL, $id=NULL ); ?></code>
Check the demo at http://popup.emc2innovation.com !
To Do list:
<ul>
<li>Add No-JS fallback support</li>
<li>Create a selection of button themes</li>
<li>Add support for different lightbox types</li>
<li>Improve handling, add PHP cookie support</li>
</ul>
Known bugs:
<ul>
<li>Recursive post shortcode call results in chaos</li>
</ul>
<h3>Configuration</h3>
EMC2 Popup Disclaimer will work straight out of the box. There’s a few options available from within WordPress, and future releases will feature themeable options.
Settings can be found in these locations:
<ul>
<li>/wp-admin/options-general.php?page=emc2-popup-disclaimer/emc2pdc-admin.php (Default settings)</li>
<li>/wp-content/plugins/emc2-popup-disclaimer/js/emc2pdc.js (Fancybox, jQuery-cookie settings)</li>
</ul>
The settings page is straightforward except for perhaps the “Restrict operation to directory:” setting. This is the operational directory of the jQuery cookie plugin – default is ‘/’, which is your entire site. To specify operation for a certain directory, type it here like ‘/store’. More jQuery-cookie settings can be found at https://github.com/carhartl/jquery-cookie.
Things of note:
<ul>
<li>Specify post ID using shortcode is optional ? if blank, it will use ID# from settings</li>
<li>Shortcode / function call will override wp_footer action</li>
<li>Debug mode will output visible settings on every included page</li>
<li>Setting an ID equal to the page you?re calling from results in mass chaos! If you set the shortcode [ emc2pdc id=”10″ ] on post ID 10 it seems to freak out a bit.</li>
</ul>

EMC2 Popup Disclaimer

EMC2 Popup Disclaimer places a specified post into a lightbox and adds buttons so that your visitors must click through to agree to your terms!

Easy Admin Notification vs EMC2 Popup Disclaimer