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.

Vikas Jhajhria

Rohit Choudhary

This plugin creates a duplicate copy of you selected theme.

Theme Duplicator

Theme Duplicator is awesome and user-friendly plugin to create copy of any theme.

This is awesome plugin to create copy of any theme

Works perfectly for copying any theme. It’s really a great and helpful plugin.

A required plugin for Developers

This plugin creates a duplicate copy of you selected theme.

Network Admin Assistant vs Theme Duplicator