Taxonomy

A mass category editor.
Allows any nodes shown on admin/content/node to have terms added or removed in bulk, using the normal 'node operations' selector.
Also provides a tab to view/edit all nodes terms individually.

With an image thumbnail, this can also be used for sorting uploaded images into galleries quickly.

Consider this module deprecated in favor of Views Bulk Operations - which offers a more cohesive interface to pretty much the same job
You may also experiment with editview or similar for mass updates.

Based on the core statistics module, which tracks general page views and node views, term_statistics keeps track of views of categories (terms) and includes a page and block for top-viewed categories.

Access control for user roles based on taxonomy categories (vocabulary, terms).

This module allows you to put nodes into series using taxonomy.

This module is no longer under active development. I'm not even sure if it's useful anymore, and would personally recommend Views for any node listing needs. However, if someone would like to adopt this module, please contact me.

This module provides node listings by vocabulary, much like taxonomy.module provides node listing by terms. It also implements vocabulary feeds, and works under the same principles as taxonomy term URLs.

About

This module was originally suggested by Nedjo Rogers on http://groups.drupal.org/node/100179. The group discussion page gathered much attention at the time, but little unification actually resulted from the discussions. I felt the concepts discussed were a good idea, and that the Autotag module would benefit from them.

The taxonomy_image module allows site administrators to associate images with taxonomy terms. With the association created, an admin can then make a call to 'taxonomy_image_display()' from their theme or other PHP code to display the appropriate image.

Taxonomy Theme allows you to change the theme of a given node based on the taxonomy term or vocabulary.

Taxonomy Theme 6.x

Taxonomy Theme 5.x has not beeen ported to Drupal 6.x, as such. For Drupal 6.x ThemeKey offers a much better approach to switching themes using theme switching rules.

Taxonomy Theme 6.x now depends on ThemeKey UI (which is part of ThemeKey) and uses ThemeKey as a back-end to do all the magic. Taxonomy Theme, itself, now simply provides the front-end.

Taxonomy Defaults allows you to assign default terms from any vocabulary to any node-type. The default terms will be pre-selected on the /node/add form, but can be edited.

If a vocabulary is marked as "Hidden" for a particular content type, then that vocabulary will not be shown on the /node/add form and the default terms will be assigned automatically and cannot be edited.

taxonomy_similar will display a "similar tags" screen anytime content has been created or updated with tags from a "Free tagging" vocabulary. This module requires no configuration. Install it, enable it, and create or edit content that has a "Free tagging" vocabulary assigned to it. The "similar tags" screen is entirely optional to the content creator - by the time it appears, the new or edited content has already been saved to the database. The content creator can edit his tags, or simply move on.