hazardcell

A newer version for WP3.0 is in the works. I would have loved to release it on time for the release of 3.0 but I’m having my finals at the moment so it will have to wait until June 2010. Will include single sign-on as well.
This plugin is for WordPress MU
This plugin basically allows you to host blogs on multiple domain names while maintaining one main site.
For example, the main site could be example.com but users will also be able to sign up for blogs on example.net, example.org or any other domain name that you choose to add.
<ul>
<li>All the sites will have the same settings</li>
<li>No extra blogs/tables are created for the additional domain names</li>
<li>All blogs will be viewable on the Site Admin blog list</li>
</ul>
Alternatively, if you would like to request a feature and/or report a bug, please visit the <a href="https://wordpress.org/tags/yet-another-multi-site-manager" rel="ugc">forum</a> or the <a href="https://plugins.trac.wordpress.org/browser/yet-another-multi-site-manager/" rel="nofollow ugc">trac repository</a>. You will have to login with your WordPress.org username and password to access these.
<h3>Known Issues/Limitations</h3>
<ul>
<li>Remote login does not work with this version</li>
<li>Only tested with VHOST installs in root directory</li>
</ul>

Yet Another Multi-Site Manager

Allows blogs to be created on multiple domain names while maintaining only one main site for all domain names.

kodeala

Reorder Multisite Sites Dropdown gives WordPress Multisite administrators a powerful tool to organize the My Sites dropdown in the WordPress Admin Bar. With this plugin, you can customize how sites appear in the admin bar so they are easier to find and better organized for your workflow. It is especially useful for WordPress Multisite networks with many sites where the default alphabetical ordering becomes difficult to manage, enhancing the existing WordPress multisite admin bar experience without modifying WordPress core functionality.
With this plugin, you can:
<ul>
<li>Reorder sites in the My Sites dropdown using drag-and-drop.</li>
<li>Manually set ordering using number input fields for quick repositioning.</li>
<li>Create groups to organize related sites together.</li>
<li>Add divider lines to visually separate sections.</li>
<li>Nest sites inside groups for better structure.</li>
</ul>
The ordering interface is available in the Network Admin under Settings > Reorder My Sites

Reorder Multisite Sites Dropdown

Adds advanced ordering controls to the WordPress Multisite My Sites admin bar dropdown, allowing administrators to organize sites with drag-and-drop,  …

Yet Another Multi-Site Manager vs Reorder Multisite Sites Dropdown