Franz Josef Kaiser

<h4>Internal Link Checker</h4>
<p>Adds a meta box to the post edit screen that shows all internal links from other posts to the currently displayed post. The plugin works out of the box.</p>


Plugin Name:		Internal Link Checker

Marcin Pietrzak

<p>Display cool, animated fly-out or fade box with related content.</p>
<p>When a reader scrolls to the bottom of a single post, page, or custom post type, an animate box will be shown allowing the reader to select the previous or random available post or posts in the selected configuration:</p>
<ol>
<li>Just previous</li>
<li>Previous in category</li>
<li>Previous in tag</li>
<li>Random</li>
<li>Related using YARPP (only post/pages)</li>
</ol>


upPrev

Great plugin. Works great, lightweight and doesn't take a lot of resources to manage. 

Great Plugin

Display cool, animated fly-out or fade box with related content.

Plugin Name: Internal Link Checker vs upPrev