Taxonomy breadcrumbs
This can be accomplished by overriding theme_breadcrumb() in your theme's template.php
An example implementation:

function mytheme_breadcrumb($breadcrumb) {

  if (arg(0) == 'taxonomy' &amp;&amp; arg(1) == 'term' &amp;&amp; is_numeric(arg(2))) {
    $breadcrumb = array();
    $breadcrumb[] = l(t('Home'), '&lt;front&gt;');
    $breadcrumb[] = l(t('Blog'), 'path/to/blog');

    $tid = arg(2);

    if ($term = taxonomy_term_load($tid)) {
      $uri = entity_uri('taxonomy_term', $term);
      $breadcrumb[] = l($term-&gt;name, $uri['path'], $uri['options']);
    }
  }

  // resume normal operation
  if (!empty($breadcrumb)) {
  // uncomment the next line to enable current page in the breadcrumb trail
    $title = drupal_get_title();
    if (!empty($title)) {
      $breadcrumb[] = $title;
      unset($title);
    }

    return '&lt;div class="breadcrumb"&gt;'. implode(' &amp;gt; ', $breadcrumb) . '&lt;/div&gt;';
  }
}