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.

DCoda

This plugin is only supported on PHP 5.2 or greater.
 
MUWidgets adds widgets to extend the standard WordPress widgets to be able to run as if on another site on the Multisite installation.
You now have a number of new widgets prefixed with the word ‘Site’ that operate the same as the standard WordPress plugins, just with the addition of a ‘Site’ option in the setup. 
You are able to select any Site on the Multisite installation that you have administration access to. 
 Just select the site and click ‘save’ now the widget is operating as if it was on the other site, enabling you to display for example the blogroll or recent posts from the main blog. 

If you are having trouble and cannot find the answers in the <a href="http://muwidgets.dcoda.co.uk/help/faq/" rel="nofollow ugc">FAQ</a> you can post your support questions to the <a href="https://wordpress.org/tags/mu-widgets" rel="ugc">WordPress Support Forum</a>
If you find Multisite Widgets useful please rate it at <a href="https://wordpress.org/extend/plugins/mu-widgets/" rel="ugc">wordpress.org</a> and please consider making a <a href="http://muwidgets.dcoda.co.uk/donate/" rel="nofollow ugc">donation</a> to help us set aside more hours to maintain Multisite Widgets
Multisite Widgets is written by <a href='http://dcoda.co.uk' rel="nofollow ugc">dcoda</a>
You can check out our other plugins <a href="https://profiles.wordpress.org/users/dcoda/" rel="nofollow ugc">here</a>
If you require a custom plugin you can contact us <a href="http://dcoda.co.uk/contact/" rel="nofollow ugc">here</a> and maybe we could write it for you.
<h3>Copyright</h3>
(c) Copyright DCoda Limited, 2007 -, All Rights Reserved.
This code is released under the GPL license version 2, available here:
<a href="http://www.gnu.org/licenses/gpl.txt" rel="nofollow ugc">http://www.gnu.org/licenses/gpl.txt</a>
There are so many possibly configurations of installation the plugin can be installed on we limit testing to a PHP 5.2+ Linux platform running the latest version of WordPress at the time of release but it is released WITHOUT ANY WARRANTY; 
 without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Multisite Widgets

Extends the standard WordPress widgets to be able to run on another blog on the site.

Multisite Random Blog Redirect vs Multisite Widgets