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.

Ko Min

A widget plugin to show the latest posts from all blog in sidebar and content area in multisite enabled WordPress sites.
Features
<ol>
<li>able to show latest posts in sidebar and content areas</li>
<li>choose list or div style (content area only)</li>
<li>support short code (content area only)</li>
<li>User can change the title of the widget as usual</li>
<li>User can limit the number of posts to show</li>
<li>Posts’ stripped down content will be shown if posts’ excerpt are empty</li>
</ol>
Note: Kindly please rate this plugin or vote the compatibility. So I could review it and improve the quality of this plugin. Appreciate your help!

Multisite Latest Posts Widget

Show the latest posts from all blogs in multisite Wordpress.

BuddyPress Sitewide Notice Widget vs Multisite Latest Posts Widget