Jonny Harris

This is a simple plugin designed to make it super easy to add custom post types RSS feed into a theme. This plugin automatically queries post types that have archives enabled and generates a markup and adds it to head.
Read more about this plugin at it’s <a href="http://www.jonathandavidharris.co.uk/scripts/custom-post-type-rss-feeds/" rel="nofollow ugc">homepage</a> .
All check out the development version on github. <a href="https://github.com/spacedmonkey/custom-post-type-rss-feed" rel="nofollow ugc">https://github.com/spacedmonkey/custom-post-type-rss-feed</a>

Custom Post Type RSS feed

This is a simple plugin designed to make it super easy to add custom post types RSS feed into a theme.

Amaury Balmer

Nicolas Juen

This plugin allow to build relation between 2 custom types (posts, page, custom), very useful for manage related content on CMS type website.
A few example use cases:
<ul>
<li>manually lists of related posts</li>
<li>post series</li>
<li>rented houses connected to agency</li>
<li>etc.</li>
</ul>
Relationships are created from a settings page from the administration console.
This plugin can not do relationships with users, you should test this excellent plugin made by scribu 
https://wordpress.org/extend/plugins/posts-to-posts/

Relations Post Types

This plugin allow to build relation between 2 custom types (posts, page, custom), very useful for manage related content on CMS type website.

Custom Post Type RSS feed vs Relations Post Types