This will automatically make tags with the tagthe.net and yahoo yql services when you save or update a post. Has the option for retagging all post.
Tagbag, takes the thought out of selecting tags for your post
This plugin allows you to tag other registered users on your blog in a comment in order to bring them into a conversation they might otherwise be miss
Goes through your archives and adds tags to your posts based on semantic analysis.
Fast and efficient post tagging using multiple tag suggestion APIs, plus mass tag suggestions and editor.
Pixboom is a simple plugin that allows you to quickly and easily tag your images with text and/or clickable links.
This plugin provides a simple [tag] shortcode.
A better tag cloud. Lots of configuration options, a widget and a shortcode to add tag clouds to posts and pages.
A very simple way to add the Thinglink script to your whole website.
Quickly and easily add links to your blog posts, which when clicked, starts up the Google Earth program at the specified location (lat/long).
Tag, caption, annotate pictures and images on your WordPress blog.
Monetize off of your tags and posts. When a person clicks on your tags a product listing related to that tag appears on your blog. When a person click
The plugin performs an analysis of your post text and suggests tags for you.
Generates interesting (and often random) links from the social networking sites based on your post tags.
Suggest Tags uses the tagthe.net tagging web service to generate a list of tag suggestions.
RSS link for this tag.