Greetings to everyone, let’s build a list with our favorite blog plugins, I’ll give the start with what I like for my wp:
All in One SEO Pack
Out-of-the-box SEO for your Wordpress blog
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
WP-o-Matic
Enables administrators to create posts automatically from RSS/Atom feeds
Search Regex
Adds search & replace functionality across posts, pages, comments, and meta-data, with full regular expression support
Random Posts
Displays a highly configurable list of randomly selected posts.
Nice Search
Redirects ?s=query searches to /search/query, and converts %20 to +
WP-PageNavi
Adds a more advanced paging navigation to your WordPress blog
AutoTag
Leverages Yahoo!’s term extraction web service to automatically tag your posts
Cheers and I hope this list will help bloggers to discover new great plugins to tune-up their wp (or other blog type)
Regards, Johnny