Henry Wright

This BuddyPress plugin sends notifications to a collection of members when you use a command to mention them. Supported commands are:
<ul>
<li>@friends</li>
<li>@group</li>
<li>@moderators</li>
<li>@administrators</li>
</ul>

Crowdmentions

This plugin makes it easy to broadcast an @ mention to an exact subset of members.



very useful

Use a command to mention a collection of members on your BuddyPress site.

wladweb

Plugun show twitter user timeline, home timeline, mentions, home timeline another user, search result by post tags, category name and any words. 
Tweets can be show in widget and also in home page between posts in main loop.

Tweettee

Plugin can show tweets in widget and in home page.

Crowdmentions vs Tweettee