Matt Wiebe

I already described it above. Use it in a development environment only!

Network Enable All Themes

It's frustrating to have to enable themes when using Multisite as a local development environment. This plugin keeps all of them activated.

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.

Network Enable All Themes vs Hyper Admins