aueda

You can embed page, category, and archive menu in your Wordperss site. You can get documentation and view demos from following site: 
http://tempspace.net/plugins/?page_id=33
If you are annoyed with consumption of large amount of window space by page, category, and archive list, this plugin will be useful.
When the bottom of the menu seems to be out of the window, the menu is “multi-columnized” automatically. Also, when the right side of the menu seems to be out of the window, the horizontal position of the menu is 
automatically adjusted.
You can change font-size, color, spacing in the admin page easily.

Page Category & Archive Menu

You can embed page, category, and archive menu in your Wordperss site. You can get documentation and view demos from following site:

Aaron Butacov

The WordPress Access Keys Plugin allows you to add access keys to your navigation menus to improve accessibility of your WordPress website.
<ol>
<li>Activate</li>
<li>Add access keys to menu items under the Appearance > menu panel.</li>
<li>???</li>
<li>Profit from having an accessible site.</li>
</ol>
For <code>wp_list_pages</code> and <code>wp_list_categories</code> support 
Download the older <a href="https://wordpress.org/extend/plugins/access-keys/" rel="ugc">Access Keys plugin</a>. The older version also allow you to add access keys to pages and categories. This works with any page or category list that is called with <code>wp_list_pages</code> and <code>wp_list_categories</code> respectively.
It is simple to use this this plugin. On the Admin panel it lists pages and categories with a current access key, and in a separate list it lists the pages and categories without access keys. Just add an access key just type a number or letter in a text box and click the save button. The categories or posts will then move to the top list, and you will feel great about be kind to your users.

Access Keys for WP Navigation Menus

Add Access Keys to WordPress 3.6 Nav menus to make your website far more accessible.

Page Category & Archive Menu vs Access Keys for WP Navigation Menus