Dmytro Shteflyuk

Permalink option of WordPress <code>%category%</code> has one great limitation – 
when this option is selected, WordPress uses category with lowest ID for 
permalink generation. This plugin is intented to bypass WordPress permalinks 
limitation and allows you to select category for permalink generation.
<h4>Support</h4>
If you have any suggestions, found a bug, or just wanted to say “thank 
you”,– feel free to email me <a href="mailto:kpumuk@kpumuk.info" rel="nofollow ugc">kpumuk@kpumuk.info</a>. 
Promise, I will answer every email I received.
If you want to contribute your code, see the Development section under 
the Other Notes tab.
<h3>Development</h3>
Sources of this plugin are available both in SVN and Git:
<ul>
<li><a href="http://svn.wp-plugins.org/scategory-permalink/" rel="nofollow ugc">WordPress SVN repository</a></li>
<li><a href="http://github.com/kpumuk/scategory-permalink/" rel="nofollow ugc">GitHub</a></li>
</ul>
Feel free to check them out, make your changes and send me patches. 
Promise, I will apply every patch (of course, if they add a value to the 
product). Email for patches, suggestions, or bug reports: 
<a href="mailto:kpumuk@kpumuk.info" rel="nofollow ugc">kpumuk@kpumuk.info</a>.

sCategory Permalink

Plugin allows to select category which will be used to generate permalink on post edit page. Use custom permalink option %scategory%.

antonioandra.de

WP htaccess Control should now really be called WP htaccess and Rewrite Control. It provides an interface to customize the htaccess file generated by WordPress but also its permalinks (author, category, archives, pagination and custom taxonomies). Have a look at the screenshot for a clearer idea of the available options.
Features:
<ul>
<li>Customizing the htaccess file generated by WordPress;</li>
<li>Removing any custom taxonomy’s slug base from permalinks;</li>
<li>Removing the category base from permalinks;</li>
<li>Removing the author base from permalinks;</li>
<li>Customizing the Author Permalink Base;</li>
<li>Customizing Paginated Permalinks (translate the “page” word on permalinks to your own language);</li>
<li>Customization (and canonization) of the Search Permalink Base;</li>
<li>Creation of Category, Author, Tag and Custom Taxonomy based archives (ex: “http://your-site.com/category/stories/2010/12”, “http://your-site.com/author/admin/2010/12/page/2” and “http://your-site.com/tag/wordpress/2010/12”), this will also work if you’ve removed the base slug;</li>
<li>Maintenance mode.</li>
</ul>
Easy to use “Suggested htaccess” rules:
<ul>
<li>Jim Morgan’s htaccess;</li>
<li>Disable directory browsing;</li>
<li>Disable and redirect image hotlinking;</li>
<li>Disable and redirect file hotlinking;</li>
<li>Force canonical url (WWW or non-WWW);</li>
<li>Limit maximum file upload size;</li>
<li>Protect wp-config.php file from access;</li>
<li>Protect .htaccess file from access;</li>
<li>Protect comments.php from spam bots coming from nowhere;</li>
<li>Set 500 error page;</li>
<li>Set 403 error page;</li>
<li>Use mod_gzip if available;</li>
<li>Use mod_deflate if available;</li>
<li>Set admin email on server generated error pages;</li>
<li>Disable ServerSignature on server generated error pages.</li>
</ul>
POT file is included, translations are welcome.
<h3>Known Issues</h3>
I still haven’t tested this under WordPress multisite, issues have however been reported.
<h3>Additional Credit</h3>
Removal of the category base is based on iDope’s WP No Category Base but extended so that it works with category archives (ie.: “http://example.com/my-category/2010/12”).
Search redirection is based on Mark Jaquith’s Nice Search but extended so that it works with custom search base (ie.: “http://example.com/search-base/search-term”).
<h3>Stable Versions</h3>
For WordPress versions above 3.9 use the plugin version 3.4.
For WordPress versions above 3.4 use the plugin version 3.3.
For WordPress versions prior to 3.4 use the plugin version 2.7.2.1.

WP htaccess Control

Interface to customize the permalinks (author, category, archives and pagination) and htaccess file generated by WordPress.

sCategory Permalink vs WP htaccess Control