Widgetopia is the best collection of widgets for wordpress with 21 of the most wanted widgets and counting!
This SEO plugin checks the content of posts/pages for the keyword density (single/phrases) while writing and is automatically setting the META-tags.
Keyword Filter Plugin Replace the sensitive keyword with specific keyword in the post content.
Syntax Highlighter ComPress is a plugin for code syntax highlighting. It loads fast on the website and code can pasted easily into WordPress.
Automatically link user defined words or sentances to a URL. Only the first match is replaced on each page.
Dynamically generates Search Engine Optimizing code for your WordPress powered site.
Use this plugin to link keywords in your blogs to other blog entries about the same subject.
GhostBloggers Keyword Density Checker returns a nice overview of your global top used keywords, their density and lists a number of relevant art
Add Meta-Tags to your site, and customize them on a post-by-post basis
帮blog翻墙.防止关键词过滤;自动给墙外图片加代理. Kill the GFW. Prevent its keyword scanning; unblock facebook/picasa/flickr images.
Checking keyword density with the SEO Live Keyword Monitor in realtime.
This SEO-Tool provides a keyword analyzer calculating the keyword density of the page/post content and generating statistics for keywords and phrases.
Display contextual keyword targeted ads from amazon, clickbank and ebay in WP Posts.
Outputs a widget of related products from an AvantLink Product Search query based on a set of site-wide or post-specific keywords.
Get Wikipedia article summary for a keyword in any language, inline with your posts and pages, with a simple shortcode and/or function.
LJ Longtail SEO is a tool that detects search engine visits and uses this information to display a list of links based on second page search results
Protect your keywords from being blocking.
This plugin can high light keyword after someone searchecd it, which supports the search engines like google, baidu, ask, yahoo&bing.
Shows your visitors your most recent tweets and current tweets around tags you're interested in. More info at: http://www.viralogy.com/
Keyword Optimizer plugin was developed so that important blog post keywords on a website could be optimized using the HTML strong, em, and u, tags.
A plugin that allows you to define keyword/link pairs. The keywords are automatically linked in each of your posts.
Fun little plugin to data mine new niche keyword ideas from Froogle and Google Suggest.
Automatically adds tags to emails, urls, Post/Page/Category Titles and any other keywords you setup.