WordPress.org

This plugin allows you to associate a unique image with each of your WordPress categories in order to prettify your pages a bit. That will make your category pages look better than 90% of the category pages out there.

Everything is configurable from the settings menu, you can use it on your index (home) page, post pages, or even your sidebar ! You can do icons only, or text and icons, and it comes with a widget for the sidebar. This wonderful plugin :

• displays one or more icons in front of your post title or wherever you want
• displays icons in the sidebar, with or without the category name, with or without the help of the widget
• includes a widget. You can use multiple Category Icons widgets, include or exclude some categories, display only icons (i.e. without the category name)...
• you can make rollover with the icons in the sidebar if you follow this tutorial
• is able to display category icons in your RSS
• will either show you where to place the little code needed (template tag) in your themes
• generates pure html code of the img tag, so it gives you the freedom of doing what you want to with the icons (customizing via CSS or not)
• generates valid XHTML (and Strict XHTML)
• can prioritize the icons display (by Oliver Weichhold)
• is translated in more than 20 languages (all the .po files are included, in case you want to update your language).
• is compatible with these powerful plugins : My Category Order, qTranslate, Recent Posts, SEO Friendly Images, Similar Posts
• is compatible with WordPress Network

There is also a Lite version.