Richard Vencu

This plugin can list a selectable number of links to the latest sticky posts, within an animated box that enters the screen when it is scrolled down more than a specified percent of the page height. Admins can set the parameters below:
<ol>
<li>the percent of vertical scroll where the animated box appears</li>
<li>the number of recent sticky posts to list</li>
<li>if the posts have thumbnail there is an option to turn on / turn off the thumbnail theme capability</li>
<li>since the sticky posts are presented this way, maybe there is no need to keep them on the front page anymore, so the third option allows to disable the sticky property of posts in the main loops</li>
<li>the module can be disabled for specific posts, pages or custom posts from the post editor via a specific metabox</li>
</ol>
Other features
<ol>
<li>when displaying a post that is sticky, the corresponding link is eliminated from the animated box</li>
<li>if the sticky posts list remains empty, the animated box is not displayed anymore</li>
</ol>

Marcin Pietrzak

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

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