dev.Fishy

EN:
Adds a simple widget to the sidebar that displays a random posts.
RU:
Добавляет простой виджет в боковую панель сайта, который отображает случайные посты.

RandPost widget

Arefly

Want some fun in blog?
Like the “I’m Feeling Lucky” Function in Google?
Install this plugin now!
This plugin can Redirect you to the Random post of your blog from a post or a page.
And it is just like “I’m Feeling Lucky”!
<h4>How to use this plugin?</h4>
<ol>
<li>
First install this plugin.
</li>
<li>
Go in to the post/page you want to redirect’s Edit Page.
</li>
<li>
Find Meta Box name “Custom Field”.
</li>
<li>
Click “Enter new”.
</li>
<li>
Enter “random” in Name Table and enter anything in Value Table.
</li>
<li>
Visit this post/page, now you will be redirect to a random post of your blog!
</li>
</ol>
Live Demo: <a href="http://www.arefly.com/try-lucky/" rel="nofollow ugc">Click Here</a> (You will go to a random post of my blog)

WP Random Post

Redirect you to the Random post of your blog from a post or a page.

RandPost widget vs WP Random Post