<p>Feed(Aggre)gator takes a list of RSS feeds and creates a single list of RSS items from those feeds to be displayed as a widget. You can select how many items you want to display and whether you want to show the entries chronologically or you want to show the latest entries from each feed listed.</p>
<p>You can also opt to display the date associated with the RSS item as well as the author of the item.</p>
<h3>Donate</h3>
<p>If you like the plugin, consider supporting the author through http://www.brownlowdown.net/webdev/feedaggregator/#donate.</p>


feedgator

Feed(Aggre)gator merges a group of RSS feeds into a single widgetized list.

wokamoto

<p>This plugin modifies RSS feeds and ATOM feeds as you want.</p>
<h4>How to use</h4>
<p>Putting the following templates into the current theme folder, then you can use the customized feed templates instead of the default ones.</p>
<ul>
<li>feed-atom.php – Atom Feed Template for displaying Atom Posts feed.</li>
<li>feed-atom-comments.php – Atom Feed Template for displaying Atom Comments feed.</li>
<li>feed-rdf.php – RSS 1 RDF Feed Template for displaying RSS 1 Posts feed.</li>
<li>feed-rss.php – RSS 0.92 Feed Template for displaying RSS 0.92 Posts feed.</li>
<li>feed-rss2.php – RSS2 Feed Template for displaying RSS2 Posts feed.</li>
<li>feed-rss2-comments.php – RSS2 Feed Template for displaying RSS2 Comments feed.</li>
</ul>
<p><strong>Note:</strong><br />
When these feed templates are not in the current theme folder, WordPress’s default feed templates will be used.</p>


Feed Template Customize

This plugin modifies RSS feeds and ATOM feeds as you want.

feedgator vs Feed Template Customize