The Taxonomy Image module (at http://drupal.org/project/taxonomy_image) is a suite of modules for associating and displaying images with taxonomy.
Our client, Big Topsy Turvy, is a blog watching big-name circus performers. They want a category view that lists blog posts matching various types of performers such as clowns, acrobats, ring masters, and so on.
We will use the standard taxonomy listing with an image displayed at the top associated with the taxonomy term. This will require creating a small custom module to work in conjunction with the Taxonomy Image module.
Note
Due to the organic nature of Drupal, it's certainly possible that by the time this goes to press, the Taxonomy Image (or another) module will handle this functionality automatically. However, this is still a good overview of how to override a theme function with a module.
First install the Taxonomy Image module. You'll also need to configure permissions giving access to users to view the taxonomy images, and...