Flooha

Adds an inputbox (for create new article) to each category page. The content of new page will contain "[[category:]]" automatically.

Helps visitors share, save, bookmark, and e-mail your pages using any service, such as Delicious, Digg, Facebook, Twitter, and over 100 more.

Shows who is editing a page you are editing.

Simple framework for protection against spambots

Prevents the creation of confusable usernames.

Adds edit assertions, for safer bot edits.

A parser-function for adding CSS files, article or inline rules to articles

Provides a dynamic view of the wiki's category structure as a tree.

This Skin is a rework of the Skin used at wiki.mozilla.org it's modified to work better with new versions of MediaWiki.

Enables the creation of JavaScript character insert boxes.

Adds a special page that provides different citation formats for a particular article.

contact form for visitors

Allows users to close the sitenotice

Outputs a bulleted list of most recent items residing in a category, or a union of several categories.

The EmbedVideo Extension is a MediaWiki extension which adds a parser function called #ev for embedding video clips from popular video sharing services.

Allow users to enable JS-based, user-provided gadgets from their preferences page.

Allows using images as icons (linkless and linked both supported)

HTML image maps

Adds a user class that allows hiding revisions.

Enhances parser with logical functions.