kgraeme

DeannaS

This plugin allows site admins to turn on and off the following widgets on the WPMU dashboard (for all users):
<ol>
<li>Primary Feed</li>
<li>Secondary Feed</li>
<li>Incoming Links</li>
<li>Recent Comments</li>
<li>Recent Drafts</li>
<li>Plugins</li>
<li>Quick Press</li>
<li>Right Now</li>
</ol>
In addition, site admins can override the primary and secondary feeds.

WPMU Simple Dashboard

This plugin lets site admins control which features are shown by default on all user's dashboards.

Emanuela Castorina

This plugin in a multisite installation shows the ID of the current site/blog in the admin bar menu. The ID of the current site/blog is linked to the site info page. 
It adds also a custom column with site id information inside the sites list table. 
It can be installed only on a multisite.

Wp Show Site ID

This plugin in a multisite installation shows the ID of the current site/blog.

WPMU Simple Dashboard vs Wp Show Site ID