display a taxonomy as an image
You can use the Entity Module which will allow you to add an image field to the taxonomy.

Then instead of displaying the term-&gt;name you'll be able to display your image.

You can create a field image field_brand_logo and get it this way :

$term = taxonomy_term_load($tid);
$brand_logo = field_get_items('taxonomy_term', $term, 'field_brand_logo');
if (!empty($brand_logo)) {
   $brand_logo_img = field_view_value('taxonomy_term', $term, 'field_brand_logo', $brand_logo[0], array('type' =&gt; 'image'));
}

print render($brand_logo_img);