Jacob McKinney

WordPress plugin for setting and displaying primary categories for posts and custom post types*.
This plugin creates a meta box on the post edit screen titled “Primary Category” containing a drop down menu populated with all categories associated with that post**. Selecting a primary category and updating the post saves this data into a custom field with a meta key of “primary-category”.
To display a list of all posts with a particular primary category, use the shortcode [primary-category name=”cat_name”] where cat_name is the name of the primary category you wish to display. If a name is not specified, the shortcode will default to all posts with “uncategorized” set as the primary category.
*Note: Custom post types must support both categories and custom fields.
**Note: As new categories are added to a post, the post must be updated before those new categories will be available for selection as a primary category.

Primary Categories

WordPress plugin for setting and displaying primary categories for posts and custom post types.

Yuriy Stepanov

The plugin adds 3 shortcodes: 
[wk_terms /] for displaying categories, tags, any other taxonomies, works through the WP_Term_Query class. 
[wk_posts /] for displaying posts, pages and any other post types, WK_posts receives data through the WP_Query class 
[wk_pages /] output of hierarchical structures of pages, posts and other types of posts, the data is obtained using the get_pages() function
Shortcodes pass all call parameters to the corresponding functions and receive the initial data set from them. 
Explore the basic parameters of calling source functions by following the links.
<a href="http://bugacms.com/wpEn/whale-kit" rel="nofollow ugc">Whale Kit</a> 
<a href="http://bugacms.com/wpEn/whale-kit-examples/" rel="nofollow ugc">Whale Kit – examples</a> 
<a href="http://bugacms.com/wpRu/whale-kit" rel="nofollow ugc">Whale Kit – по русски</a>

Whale-Kit

Three alternative to standard widget Categories, Recent Posts and Pages.

Primary Categories vs Whale-Kit