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.

Slate Blank

Wiki Style Search will cause WP’s search to go directly to a page or post if a page or post’s title matches the search query; otherwise search results will display as usual. Plugin makes search function similar to that of Wikipedia.
For Example:
<ul>
<li>A search query of ‘spider’: http://thelargest.net/?s=spider takes you to http://thelargest.net/spider</li>
<li>A search query of ‘cruise ship’: http://thelargest.net/?s=cruise+ship takes you to http://thelargest.net/cruise-ship</li>
</ul>
Test more at <a href="http://thelargest.net" rel="nofollow ugc">The Largest</a>.
Please see more information at: http://thelargest.net/about/wiki-style-search-plugin
Plugin brought to you by <a href="http://slateblank.com" rel="nofollow ugc">Dallas web design</a> firm, Slate Blank.

Wiki Style Search

Wiki Style Search bypasses search results and directs users directly to an article if an article name matches their query.

Wikipedia for tag pages vs Wiki Style Search