copperblade

Update: If you need more functionality please see the next generation of this plugin at https://wordpress.org/extend/plugins/network-latest-posts/
Creates a widget to show a list of the most recent posts across a WordPress MU installation. It shows the most recent post from each blog. This plugin is based on the work of many authors.
This works on previous versions of WPMU, but not on previous versions of WordPress (where it doesn’t make sense).
<h3>Options</h3>
<ul>
<li>Number of posts to show – list this many posts.</li>
<li>Number of days to limit – only go back this number of days to get posts. Set to -1 for no limit (default).</li>
</ul>

Multisite Recent Posts Widget

Creates a widget to show a list of the most recent posts across a WordPress MU installation.  It shows the most recent post from each blog.

3dperuna

WPMU has great themes and plugins. Unfortunately, many, if not most, come with a nag notice that admins see about installing their notifications dashboard plugin. If you’ve bought one plugin for your site this is probably overkill. If you’re a developer you don’t need this on your client’s sites.
This is a simple plugin that removes the notice. The 1.3 version has been checked against WP 4.4 and recent WPMU plugins, but still should be backwards compatible with older versions of WPMU plugins.
Note: If you do decide to you install the WPMU notifications plugin, please deactivate this one first. Errors may occur if you don’t.
If you like this plugin consider donating: http://www.protospace.com/wpmu-no-nag-plugin/

Remove WPMU Dashboard Install Nag

Works as advertised. Now, why a plugin should be needed for this is another question altogether, and installing and activating this plugin is no substitute for filing an RFE to either add a close button to those annoying nags or a switch to turn them off (and their pref doesn't always work, apparently).
Thanks for this!



Simple and to the point

This plugin removes the nag notice at the top of WPMU plugins and themes.

Multisite Recent Posts Widget vs Remove WPMU Dashboard Install Nag