Aaron D. Campbell

Used to create a customizable rotating slideshow highlighting certain posts or 
pages. You can choose which posts or pages are featured by simply checking a 
checkbox on the write posts/page screen. The plugin uses the new post thumbnail 
functionality added in WordPress 2.9.
Requires PHP5.

Featured Content Showcase

Used to create a customizable rotating slideshow highlighting certain posts or pages.  Uses jQuery, which comes with WordPress (no conflicts).

linkhousemedia

This plugin was initially designed as a theme function but we thought it might come in handy for someone else. It is designed to use the following plugins:
<ul>
<li><a href="https://wordpress.org/extend/plugins/custom-post-type-ui/" rel="ugc">Custom Post Type UI</a></li>
<li><a href="https://wordpress.org/extend/plugins/taxonomy-images/" rel="ugc">Taxonomy Images</a></li>
</ul>
Of course you can create your own custom post types and taxonomies but the Custom Post Type UI plugin makes very light work of it.
The plugin creates a widget for adding featured posts. There are other plugins that do this but Featured Custom Posts allows for custom post types and taxonomies. It was created to show featured products that were created as custom post types.
Features
<ul>
<li>Select number of posts to display (default: 10)</li>
<li>Post Type</li>
<li>Custom Taxonomy</li>
<li>Custom Taxonomy Term</li>
</ul>
New In Version 1.1
<ul>
<li>Added Permalink Base for post URL (Defaults to post’s GUID)</li>
<li>Added Post Title as the link text if Taxonomy Images plugin isn’t present</li>
</ul>
Example Usage
Custom Post Type: “products” 
Taxonomy: “product-tags” 
Taxonomy Term: “featured”
In this example our custom post type of “products” allows us to add products in a similar way to posts. Now with our custom taxonomy of “product-tags” we can tag our products with the tag “featured”. Plug this information into the widget via the wp-admin area and you’re all set!
Future Updates
<ul>
<li>Allow for multiple taxonomy terms</li>
<li>Add thumbnail size support</li>
</ul>

Featured Custom Posts Widget

Widget that allows custom post types and taxonomies to be displayed.  Works well with Custom Post Type UI and Taxonomy Images plugins.

Featured Content Showcase vs Featured Custom Posts Widget