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.

Slava Abakumov

Plugin will transform wrong months’ cases (in date) to proper ones (according Russian grammar rules).
Examples: 
* not “28 September” but “28 сентября” (Eng->Ru); 
* not “28 Сентябрь” but “28 сентября” (incorrect Ru->correct RU)
Visit <a href="http://cosydale.com" rel="nofollow ugc">CosyDale.com</a> for more information.

BuddyPress Russian Months

Plugin will transform wrong months' cases (in date) to proper ones (according Russian grammar rules).

Multisite Recent Posts Widget vs BuddyPress Russian Months