Vii Studio

Vii Related Posts gives you a widget to output lists of posts related to the current post. You get to decide how the posts are related (random, categories, tags,…) and a whole lot more.
A ViiStudio plugin.
<h4>Features</h4>
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Speed 
Unlike other related posts plugins, Vii Related Posts is super fast. It doesn’t run resource-intensive algorithms on your database and it doesn’t bog down your server. If you’re looking for a plugin that’ll run through all your content and match related posts word-for-word, there are plenty of good ones out there. If you’re looking for a simple, lightning-fast related posts plugin, you’re in the right place.
</li>
<li>
Display related posts as post thumbnails, links or excerpts.
</li>
</ul>
<h4>Settings</h4>
You can easily configure Vii Related Posts with the following settings. These settings are directly configurable in each widget.
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<li>
Title 
The title of your widget. Give it blank when you need to hide the widget title.
</li>
<li>
Number of posts to show 
The total number of posts you would like to show in each section.
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<li>
Related By 
Choose the method by which you want to show related posts. You can choose random, lasted posts, popular posts (by comments), post have same tag, or post have following tag. This field automatically populates with all available possibilities.
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Tag (optional) 
When you choose related by post have following tag, specify custom tag in this field.
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</ul>

Vii Related Posts

Reduce bounce rates by display related (same category, same tag, specify tag), lasted, popular (comment count) or random posts to your site in the sim …

Ryan

Adds a shortcode, series-tag, that you can use to create a list of all posts 
that are tagged with whatever tag you pass in.
Series Tag was written to allow you to tag a series of posts with the same tag, 
and then easily link between them without having to manually create links at the 
bottom of each post.
Links are created in date published order starting at the earliest date. All post 
titles are links to the permalink of the post except for the current post which just has its title displayed.
For help or more info, visit <a href="http://www.nutt.net/tag/series-tag/" rel="nofollow ugc">Nutt.net</a>

Series Tag

Adds a shortcode so you can easily create a list of all posts with a specific tag. Written to make it easy to link between a series of posts.

Vii Related Posts vs Series Tag