channeleaton

For large multisite installations of WordPress, it’s easy to let user management go by the wayside. Many times we forget to disable or remove old user accounts, leaving our sites open to users who are no longer part of our organization.
Mass-Disable Users (MDU) aims to fix that.
MDU allows super-administrators to disable old users while retaining all of the author information. This is especially important for news sites.
How does it work?
MDU takes a list of email addresses (in CSV format) and compares it to the existing WordPress users database then any users who do not exist in the CSV file are demoted to Subscriber in every blog!
NOTE: This plugin only works on multisite!

Mass-Disable Users plugin for WordPress

Allows network admins to disable users via CSV while retaining all author information.

scribu

AppThemes

With this plugin, super-admins can:
<ul>
<li>view any theme on any site, without enabling it</li>
<li>access any site through Admin Bar -> My Sites, without having a role on it</li>
</ul>
Intended for <a href="http://scribu.net/wordpress/the-future-of-multisite.html" rel="nofollow ugc">small Multisite installs</a>.

Hyper Admins

Simplify administration tasks for super-admins.

Mass-Disable Users plugin for WordPress vs Hyper Admins