mmfilesi

This plugin shows in the sidebar n post related with the same category(s) of post being viewed. 
The result can be random or chronological order.
Este plugin es un widget que se incluye en el sidebar. Muestra n entradas relacionas con la entrada que se ha cargado. 
Los resultados pueden ordenarse de forma aleatoria o por orden cronologico.
<h3>Donations</h3>
http://www.mmfilesi.com

mmfilesi-random-post

This plugin shows in the sidebar n post related with the same category(s) of post being viewed.

Scribit

With Random plugin you can insert into your WordPress website one or more random contents coming from your posts. 
The source contents can be pages, posts or custom post types. 
You can display information in many different ways: 
* A list of post titles 
* One or more full contents or excerpts 
* Raw URLs to posts permalink

Random

This plugin give to your website the possibility to get random content for specific posts types. You can use to give to your visitors random posts, or random woocommerce products for your clients.
Very useful in my opinion.

Wikipedia style!

Random, a great plugin designed to insert random contents, posts and other types, into your website. Enjoy its shortcodes!

mmfilesi-random-post vs Random