tiredofit

Allows you to randomly visit a blog in your multisite network by appending ?randomblog at the end of your URL string. 
You can exclude by blog ID, mature or public status, and even change the string to whatever you like. 
View a working demo at <a href="http://www.bicycletouringhub.com?randomblog" rel="nofollow ugc">http://www.bicycletouringhub.com?randomblog</a>
<h3>Contact and Credits</h3>
Written by Dave Conroy (<a href="http://www.tiredofit.ca/?ms-random-blog" rel="nofollow ugc">www.tiredofit.ca</a>, e-mail ‘dave’ at ‘tiredofit dot ca’), 2012-02. 
Written inside of a tent while he bicycles the world for <a href="http://www.bicycletouringhub.com" rel="nofollow ugc">www.bicycletouringhub.com</a>

Multisite Random Blog Redirect

Allows you to randomly visit a blog in your multisite network by appending ?randomblog at the end of your URL string.

DanielTulp

<h4>Major overhaul</h4>
As of version 2.0 CNP allows you to easily embed posts from other websites in the same WordPress network with a shortcode builder that is available above your editor.
The manual way of entering the shortcode is still available, but you can chooses whichever you prefer.
Also included from version 2.0 is an options page where you set certain security measures: 1. You can restrict embedding of content to only the original author of the post (does not apply to administrators) 1. You can disallow other websites in the WordPress network to embed posts from your website
<h4>Usage</h4>
This plugin is useful if you have a wordpress network (multisite) and you want to display (embed) a post or a category of posts that is on another website in the same network.
Use the shortcode builder above the editor or type the shortcode in manually:
<pre><code>[cnp blogid=1 postid=1] </code></pre>
<h4>Attributes</h4>
Mandatory
blogid is the ID of the blog you wish to pull the post from (go to Network->Sites and hover over the site to view the ID).
Instead of postid= you can also use catid= to display all posts from a category.
Optional
header=1 -> header number (i.e. h1 ), no title if you set it to 0 (default is 2)
excerpt=true -> if you only want to display excerpts with read more links to the post on the other website
numberofposts=5 -> for displaying a certain number of posts from a category (default is 5)
titlelink=false -> if you don’t want the title to have a permalink (default is true)
Working with other plugins
If you want to display a plugin through a shortcode that is in one of the posts that you are displaying, make sure that the plugin is also active on the network site where you use CNP.
Note: not all plugins will work. Post about it if you find some that do and also that don’t.

Cross-Network posts

Embed a post or a category of posts that is within another website on the same Wordpress network (multisite).

Multisite Random Blog Redirect vs Cross-Network posts