faebu

With the Thickbox Announcement you easily can set-up an announcement, which will be displayed in a thickbox (lightbox). 
Several options let you control the apperenace and the frequency of the announcement. You can display any external 
content using an iframe or an inline content which can be edited using the standard wordpress editor.
<h4>Update Information</h4>
I’ve renamed my plugin since the plugin named looked very irritating. Since Version 1.0.3 the plugin is simply called Thickbox Announcement. 
If you are still using Version 1.0.2 no updates are displayed in the plugin overview of your wp installation. To perform an update 
you have to use the function Add New and search for this plugin. Click on Update to perform the automatic update.

Thickbox Announcement

With the Thickbox Announcement plugin you easily can set-up an announcement, which will be displayed in a thickbox (lightbox).

Christian Schenk

Allows you to embed ThickBox into your blog. Simply insert ThickBox compliant markup 
where ever you want and you’re all set. It is a pretty lightweight plugin but here 
are some of its features:
<ul>
<li>comes with an expert mode that allows you include the JavaScript and CSS for ThickBox only on those pages that actually need it</li>
<li>you can opt to use the script and style already bundled with WordPress</li>
<li>automatically adds the correct class attribute when using the gallery shortcode</li>
<li>and also contains SmoothBox</li>
</ul>
<h3>Licence</h3>
This plugin is released under the GPL.

ThickBox

Embed ThickBox into your posts and pages.

Thickbox Announcement vs ThickBox