This plugin allows you to easily insert a wide variety of links into your wordpress documents with the following tag style:
[ln wikipedia]topic[/ln]
[ln php]htmlentities[/ln]
[ln amazon]978-0321396853[text]Eclipse Web Tools Platform[/text][/ln]
Or you can add links by clicking the ‘ln’ button inside of the wysiwyg editor. This will bring up a dialog box where you enter in the necessary data for that particular link
New link types can be easily added and existing links can be easily modified from the wordpress options page.
The following types of links are currently supported by default (with more on the way):
<ul>
<li>amazon</li>
<li>gravatar</li>
<li>php</li>
<li>twitter-rss</li>
<li>wikipedia</li>
<li>wppost</li>
</ul>

linkle

Easily embed links to wikipedia topics, amazon book sales, php documentation, and more with [ln linktype]topic[/ln].

Haldaug

This plugin creates a widget that displays excerpts from Wikipedia on the tag pages (the template tag.php). The user can specify multiple languages for the plugin to query using the Wikipeida API. The language that has an article that matches the tag has its article displayed.
<h3>Credits</h3>
This widget is based on the WordPress-Wikipedia-Widget by patlockley: <a href="https://github.com/patlockley/WordPress-Wikipedia-Widget" rel="nofollow ugc">WordPress-Wikipedia-Widget</a>

Wikipedia for tag pages

A widget that displays excerpts from Wikipedia articles relevant to the tag on tag-pages. Support for multiple languages.

linkle vs Wikipedia for tag pages