CSS Compress Automatically removes comments, new lines, tabs, and gzip compresses (GZIP) any CSS file called with "<?php bloginfo('stylesheet_url'); ?>"
Current Mood - Adds a "Current Mood" icon to each post at end of post context.
DashBar - Display a WordPress.com-like navigation bar for logged users with quick links to administration tasks related to the current page.
Digg This - Digg this wordpress plugin is a plugin that detects incoming links from Digg.com to your wordpress post and automaticaly display a link back to the Digg post
Dokuwiki Markup - Use the power and simplicity of the dokuwiki markup in your posts and pages
DonkieQuote - Displays a random quote from a database on your blog.
DownOnMe - Rewrites header tags one level down (h2 -> h3, etc.) in multipost blog pages.
Exec-PHP - Allows <?php ?> tags inside your Wordpress posts and executes the code inside of it just like you normally write and run code inside of any PHP file.
FancyTooltips - Replace standard browser tooltips with customizable, dynamic ones.
favatars - adds favicons next to comments/pingbacks/trackbacks
feedList - displays any RSS or Atom feed on your webpage (del.icio.us, 43 things, tada, news, etc..) (formerlly rssLinkList)
KittensGeoPlugin - adds geographic information (latitude, longitude) to each post
Kramer - turns Technorati inbound links and validated referers into pingbacks for each post, as well as provides a function to show inbound links to the weblog itself
PostLocation - adds address information to each post for providing links to services like Map Quest and Google Maps
Post Levels - Allows you to restrict access to posts based upon a registered user's level. Only registered (and logged in) users with a level greater than or equal to the post level may view the post.
Post Teaser - Generates a "teaser" preview of each post with information about it
PreFormatted - Stores posts & comments in formatted form rather than processing them every time a page is loaded.
Sid's MP3 Player can display a Flash player for mp3 files. Either you give your visitors some background music in the sidebar, or you have a preview of podcasts (fully automatically)
Text Control - Take complete control of text formatting options on your blog: Formatting and encoding per post, globally on posts, and globally on comments.
ThemeSwitcher - Allow users to switch among available themes.
Travelog - Input and organize information about the places you've been, and associate individual posts (or text within posts) with these locations. Location information and maps can then be shown for each post.
The Truth Laid Bair Ecosystem Cache - Displays your site's status in TTLB Ecosystem,replacing the javascript tag that the TTLB Ecosystem currently provides. It caches the results every 24 hours so as to reduce load times.
UltimateTagWarrior - Tagging; but ultimate and a warrior. Tagging for taggings sake, rather than technorati specific.
UrlCache - provides a PHP function caches URLs locally.
Usermeta - Adds API for WordPress 1.5 so that arbitrary meta data can be associated to users.
Userextra - Extends user profiles to include admin-defined attributes, and provides for category access controls with user-level granularity
Verificador - tests the name, email and comment fields, before you send it.
VideoPop - Create links that open videos in a popup window.
vimcolor - Color the syntax of 200+ languages including PHP, Perl, C, HTML, Fortran, Haskell, Java, etc.