Mindvalley

This shortcode will allow you to include the content from any posts or pages.
Shortcode usage:
<ul>
<li>[mv_include id=’4′] (best for performance)</li>
<li>[mv_include slug=’the-post-slug’]</li>
<li>[mv_include path=’http://www.example.com/parent-page/sub-page/’]</li>
<li>[mv_include path=’parent-page/sub-page’]</li>
</ul>
The plugin also create a special post type that can be used for content that are for inclusion only.

Mindvalley Include Post Content

Creates shortcode [mv_include] to include content from another post/page.

oltdev

This plugin enables page or post authors to scrape content from mediawiki pages and appending it to their pages. 
It works by scraping content from mediawiki pages by going to a special mediawiki page url.
For example http://en.wikipedia.org/wiki/Wordpress?action=render
The content rendered on the final page or post will always be the newest content, however it is not searchable via regular WordPress search form.
Use case: 
This plugin is great for adding documentation to your site. 
Since wordpress.org is using mediawiki for the codex you could potentially display wordpress codex pages on your site without much effort, just enter the full url of the specific wordpress codex page.
Enjoy

Wiki Append

Append a mediawiki page at the end of the regular wordpress page.

Mindvalley Include Post Content vs Wiki Append