Jennifer M. Dodd

The BuddyPress default theme provides users with an area in the sidebar for the 
display and dismissal of sitewide notices. This plugin wraps that code in a 
widget so that users can easily add that functionality to their own widget-ready 
sidebar without editing <code>sidebar.php</code>.
<h3>Credits</h3>
Development funded, in part, by Ariel Meadow Stallings and the Offbeat Empire.

BuddyPress Sitewide Notice Widget

Wrap the BuddyPress sitewide notice in a widget.

BuddyDev

Brajesh Singh

This plugin is deprecated. It is not compatible with WordPress 4.0+ . Please do not use it. We won’t be able to support it in future. 
Multisite Global Terms allows all sites across a WordPress multisite network to share the categories/tags/terms.
It uses the main site’s table to store all the terms. 
Please visit the blog post on <a href="http://buddydev.com/wordpress-multisite/want-global-categories-tags-taxonomies-across-wordpress-multisite-network/" title="Multisite Global Terms" rel="nofollow ugc">BuddyDev</a> for support or to ask a questions.

Multisite Global Terms

Thanks! Didn't install, but used your code!!! 

Nice!

I didn't install this plugin, but I'm using your code on a new multisite build. Thank you for writing this plugin as it was exactly what I was looking for.

-Steven

This is exactly what I was looking for!

Allow global terms across all blogs on a multisite installation.

BuddyPress Sitewide Notice Widget vs Multisite Global Terms