JoshuaPack

Why choose this plugin?
<ul>
<li>404 pages not working? </li>
<li>Would you like to have a custom 404 page? </li>
<li>Would you like the 404 page to be a static page? </li>
<li>Do you need to have a WordPress CMS page as your 404 page?</li>
</ul>
This plugin does it!
This a rebel plugin that does not use WordPress’s 404 hook. It was developed for themes or plugins that cause issues with the hook itself.
For more information see FAQ page.

HTD 404

This plugin will simply allow you to point to a page to serve up if you get a 404 error. Also it marks it as 404.

cubecolour

Stomps the footer element to the bottom of the visible page on short pages.
<h4>Usage:</h4>
When the height of the document body is less than the internal height of the browser window, this plugin prevents a gap appearing between the footer element and the bottom of the visible page by fixing the footer to the bottom of the page.
If the plugin does not have any effect on the footer of any short pages, this may be due to your footer not being marked up as an HTML5 ‘footer’ element. It may have instead been marked up as another element such as a div with a class or id of ‘footer’, ‘site-footer’, or something else.
If this is the case you can add a constant to define the CSS selector for your footer element by editing your wp-config.php by adding the line:
<pre><code>define( 'STOMP_FOOTER_ELEMENT', '.site-footer' );
</code></pre>
before the line:
<pre><code>/* That's all, stop editing! Happy blogging. */
</code></pre>
In this example the value of STOMP_FOOTER_ELEMENT is ‘.site-footer’

Stomp

Stomps the footer element to the bottom of the visible page on short pages.

HTD 404 vs Stomp