SitePoint has a nice list of wordpress plugins.
DoFollow
top commentators
WP Most Commented
rotating header
rotating sidebar images
random posts
Featured Content Plugin
Multi Page Toolkit
breadcrumb navigation plugin
a bunch of other useful plugins
Viper’s Video Quicktags
Seesmic WordPress Plugin
MobilePress
All in One SEO Pack
SitePoint » More than 10 “Must Have” WordPress Plugins
These plugins help you transform a blog into a genuine rich-media experience by adding to your site interactive elements that appeal to your community.
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