elebail

Creates 4 feeds :
trdf => rdf in theme (template : feed-rdf.php)
trss => rss 1.0 in theme (template : feed-rss.php)
trss2 => rss 2.0 in theme (template : feed-rss2-comments.php and feed-rss2.php)
tatom => atom in theme (template : feed-atom-comments.php and feed-atom.php)
Those feeds look for a feed template into the theme directory. 
If no template is found into the theme directory the feed uses the default wordpress feed template.
This plugin has been tested with WP2.6.5, WP2.8.4 and WPmu2.8.4
<h3>Update Log</h3>
1.0.1 : Performance improovment.
1.0.0 : Test under WP2.6.5, WP 2.8.4, WPmu2.8.4
0.0.1 : plugin initial creation.

Feeds in Theme plugin

Invoicepress

Fahad Mahmood

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Author: <a href="https://www.androidbubbles.com/contact" rel="nofollow ugc">Fahad Mahmood</a>
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Project URI: <a href="http://androidbubble.com/blog/wordpress/widgets/rss-feed-widget" rel="nofollow ugc">http://androidbubble.com/blog/wordpress/widgets/rss-feed-widget</a>
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License: GPL 3. See License below for copyright jots and tittles.
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RSS Feed Widget is a free WordPress plugin for rss feeds display. It is simple to use as after installation you see a menu item under settings. Easily to get started with this plugin, select image size for your feed and save changes. For more customization, you can install Chameleon and choose desired style. This plugin also provides to filter or mute words/text/sentences etc. To filter any word/text/sentence open filter tab and enter word/text/sentence as one per line. 
You can also choose various image sizes for your feed like thumbnail, medium, large or post thumbnail etc. It also provides the facility of creating shortcode based pages. The shortcode tab describes that how can you create shotcode based pages. The most important and special feature is Advanced Settings. Advanced settings tab allows you to reach custom tag in strange XML based feeds for images.
Important! 
Visit my blog and suggest good features which you wana see in this plugin.
<h4>Tags</h4>
feed, facebook, youtube, shortcodes, slider, image, widget, page, techcrucnch, news, updates, aggragator, slideshow, feedly
How to use shortcodes for content pages? 
<iframe loading="lazy" class="youtube-player" width="750" height="422" src="https://www.youtube.com/embed/QCLNXfPOsQo?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox"></iframe>
<h3>License</h3>
This WordPress Plugin is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or any later version. This free software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this software. If not, see http://www.gnu.org/licenses/gpl-2.0.html.

RSS Feed Widget

I've had to contact this author a couple of times now to call out some bad coding. I wouldn't recommend this plugin, find a different one, or make sure you go through the code essentially any time its updated. 

Some sloppy code here

RSS Feed Widget with customizable slider. Feed title, description, image, censorship and a few other features which you can use.

Feeds in Theme plugin vs RSS Feed Widget