These are the WordPress plugins I've had a little experience with. This list doesn't necessarily imply a recommendation, but hopefully it will be a good starting point for WordPress users. Please feel free to add to this page or leave a comment at the bottom. Thank you! -- Pete
Bulk Delete - Bulk delete posts from selected categories or tags. Use it with caution.
Bulk Move - Bulk move posts from selected categories or tags.
Disable WordPress Core Update - Disables the WordPress core update checking and notification system.
Extended Comment Options - This plugin allows you to switch comments and/or pings on or off for batches of existing posts.
Flickr Gallery - Use easy shortcodes to insert Flickr galleries and photos (and videos) in your blog.
flickr-slideshow-wrapper - Including flickr slideshows.
Google XML Sitemaps - This plugin will generate a sitemaps.org compatible sitemap of your WordPress blog which is supported by Ask.com, Google, MSN Search and YAHOO.
List Installed Plugins - Lists your currently installed and activated plugins. Plugins can be hidden form the list if desired. Options page allows you to set a page to display the list on, change the format, and configure other options. Helped create this page! Also see: WP-PluginsUsed, pluginsUsedPlugin
Maintenance Mode - Adds a splash page to your blog that lets visitors know your blog is down for maintenance. Logged in administrators get full access to the blog including the front-end.
Multi-level Navigation Plugin - A WordPress plugin which adds a multi-level CSS based dropdown/flyout/slider menu to your WordPress blog.
Search Meter - Keeps track of what your visitors are searching for.
WP-DB-Backup - WordPress database backup creates backups of your core WordPress tables as well as other tables of your choice in the same database.
WP-DBManager - Manages your Wordpress database. Allows you to optimize database, repair database, backup database, restore database, delete backup database , drop/empty tables and run selected queries. Supports automatic scheduling of backing up and optimizing of database.
WP-FLV - This plugin eases insertion of Jeroen Wijerings FLV Video Player.
WP Security Scan - Perform security scan of WordPress installation.
WP Super Cache - Very fast caching plugin for WordPress.