mogita

NOTE: ONLY works with multisite (aka WordPress Network) mode for now.
A super-easy-to-use Multisite WordPress news broadcasting tool for the Super Admin of the Network.
This plugin can be helpful for the Super Admins to push a notification, some kind of messages, even some Ads if they like, to every site admins who registered under your Multisite WordPress network. The added widget will go to the first place of all widgets, unless the site admins move it elsewhere.
This is a very simple task but yet no plugins ever met my simple need, so I made one for myself, and hope it helps you too.
Key Features:
<ul>
<li>Add a widget to every site admin’s dashboard (by Super Admin only)</li>
<li>Support HTML content</li>
<li>Comes at the top of all widgets</li>
<li>Site admins can move or hide it as they wish</li>
<li>Multi languages support (available in English and Chinese till now)</li>
</ul>
You can find the configuration page at Manage Network -> Settings -> Dashbaord Broadcast.

Multisite Dashboard Broadcast

Place a widget on top of every site's dashboard under the same Multisite installation, containing whatever content the Super Admin writes.

feedmeastraycat

WordPress removes the Update Services ability (Settings – Writing) when you create a network (aka enables WordPress MU/Multisite). 
Activate this plugin to get it back.
Note: This is only for WordPress setups with a network, aka multiple sites, aka multisites, 
aka WPMU in WordPress 3 and later.
This plugin might work with older WordPress MU sites. I haven’t tested it though. If you do, please 
let me know how it turned out.
<h3>Files</h3>
<ul>
<li>/activate-update-services/activate-update-services.php</li>
<li>/activate-update-services/README.txt</li>
</ul>

Activate Update Services

WordPress removes the Update Services ability when you create a network. Activate this plugin to get it back.

Multisite Dashboard Broadcast vs Activate Update Services