Roy Tanck

This plugin will help you:
<ol>
<li>Find plugins and themes that are not active on any blog.</li>
<li>Determine the impact in case a theme/plugin needs to be upgraded, removed or reconfigured.</li>
<li>See if a widget is in use on any blogs, and track down where.</li>
<li>Find users who do not have a role on any site (and are not network administrators).</li>
</ol>
This plugin currently does nothing on single-site WordPress installs.

Network Admin Assistant

Helps you manage a WordPress network by displaying useful statistics.

jimaek

jdorfman

This plugin allows you to easily integrate <a href="http://www.bootstrapcdn.com" rel="nofollow ugc">BootstrapCDN</a> in your WordPress website.
BootstrapCDN is a free and public content delivery network. Users of BootstrapCDN can load CSS, JavaScript and images remotely, from its servers. Bootstrap uses NetDNA’s global content delivery network, which makes websites using its service resilient to unexpected surges in web traffic.
Use this plugin to scan your WordPress website and rewrite all Bootstrap files to CDN hosted links.
Benefits:
<ul>
<li>Faster website</li>
<li>Less requests to your server</li>
<li>Less bandwidth consumed</li>
</ul>
Features:
<ul>
<li>Rewrite all URLs on the fly without changing any source code</li>
<li>Auto-update to latest Bootstrap version</li>
<li>Works with all popular caching plugins</li>
<li>Optional FontAwesome integration</li>
<li>Manually select the version you want to load</li>
</ul>
BootstrapCDN is a free service by <a href="http://www.maxcdn.com" rel="nofollow ugc">MaxCDN</a>

BootstrapCDN – WordPress CDN Plugin

The official WordPress plugin of BootstrapCDN by MaxCDN.

Network Admin Assistant vs BootstrapCDN – WordPress CDN Plugin