diff --git a/classes/ComicPressRelatedPosts.inc b/classes/ComicPressRelatedPosts.inc
new file mode 100644
index 0000000..248d8b3
--- /dev/null
+++ b/classes/ComicPressRelatedPosts.inc
@@ -0,0 +1,126 @@
+<?php
+
+require_once('ComicPressStoryline.inc');
+
+class ComicPressRelatedPosts {
+	var $related_categories;
+
+	function shortcode_related_comics($attrs = '') {
+		$rp = new ComicPressRelatedPosts();
+		return $rp->_handle_shortcode(
+		  extract(ComicPressRelatedPosts::_handle_shortcode_attrs($attrs)),
+		  __('Related Comics', 'comicpress'), true
+		);
+	}
+
+	function shortcode_related_posts($attrs = '') {
+		$rp = new ComicPressRelatedPosts();
+		return $rp->_handle_shortcode(
+		  extract(ComicPressRelatedPosts::_handle_shortcode_attrs($attrs)),
+		  __('Related Posts', 'comicpress'), false
+		);
+	}
+
+	function _handle_shortcode($attrs, $title, $is_in_storyline) {
+		global $post;
+
+		if (is_object($post)) {
+			if (isset($post->ID)) {
+				$this->_setup_categories($is_in_storyline);
+				$tags = $this->_extract_tag_ids($post->ID);
+
+				if (!empty($tags)) {
+					$posts = $this->_do_tags_query($post->ID, $tags, $attrs['limit']);
+					if (!empty($posts)) {
+						return $this->build_post_table($title, $posts);
+					}
+				}
+			}
+		}
+
+		return '';
+	}
+
+	function _handle_shortcode_attrs($attrs) {
+		return shortcode_atts(array(
+			'limit' => '5',
+		), $atts);
+	}
+
+	function _new_comicpressstoryline() { return new ComicPressStoryline(); }
+
+	function _setup_categories($is_in_storyline = true) {
+		$storyline = new ComicPressStoryline();
+		$storyline->read_from_options();
+		$storyline_categories = $storyline->build_from_restrictions();
+
+		if ($is_in_storyline) {
+			$this->related_categories = $storyline_categories;
+		} else {
+			$this->related_categories = array_diff(get_all_category_ids(), $storyline_categories);
+		}
+	}
+
+	function build_post_table($title, $posts) {
+		$output = array();
+		if (!empty($posts)) {
+			$output[] = '<div class="related_posts">';
+				$output[] = '<span>' . $title . '</span>';
+				$output[] = '<table class="month-table">';
+				foreach ($posts as $post) {
+					if (array_intersect($this->related_categories, wp_get_post_categories($post->ID))) {
+						$output[] = '<tr><td class="archive-date" align="right">' . date('M j, Y', strtotime($post->post_date)) . '</td>';
+						$output[] = '<td class="archive-title"><a title="' . esc_attr(get_the_title($post)) . '" href="' . esc_attr(get_permalink($post)) . '">' . esc_html(get_the_title($post)) . '</a></td></tr>';
+					}
+				}
+				$output[] = '</table>';
+			$output[] = '</div>';
+		}
+		return implode('', $output);
+	}
+
+	function _extract_tag_ids($post_id) {
+		$output = array();
+		foreach (wp_get_post_tags($post_id) as $tag) {
+			$output[] = $tag->term_id;
+		}
+		return $output;
+	}
+
+	// @codeCoverageIgnoreStart
+	function _do_tags_query($post_id, $tags = array(), $limit = 5) {
+		global $wpdb;
+
+		if (!empty($tags)) {
+			if (empty($limit)) {
+				$limit = 5;
+			}
+
+			// Do the query
+			$q = "SELECT p.*, count(tr.object_id) as count
+					  FROM
+			        $wpdb->term_taxonomy AS tt,
+			        $wpdb->term_relationships AS tr,
+			        $wpdb->posts AS p
+					  WHERE
+					    tt.taxonomy ='post_tag' AND
+					    tt.term_taxonomy_id = tr.term_taxonomy_id AND
+					    tr.object_id  = p.ID AND
+					    tt.term_id IN (%s) AND
+					    p.ID != %d AND
+					    p.post_status = 'publish' AND
+					    p.post_date < NOW()
+						GROUP BY tr.object_id
+						ORDER BY count DESC, p.post_date DESC
+						LIMIT %d";
+
+			return $wpdb->get_results($wpdb->prepare($q, implode(',', $tags), $post_id, $limit));
+		}
+		return false;
+	}
+	// @codeCoverageIgnoreEnd
+}
+
+add_shortcode('related_posts', array('ComicPressRelatedPosts', 'shortcode_related_posts'));
+add_shortcode('related_comics', array('ComicPressRelatedPosts', 'shortcode_related_comics'));
+
diff --git a/functions/relatedcomics.php b/functions/relatedcomics.php
index 3e6cb8c..09b7e13 100644
--- a/functions/relatedcomics.php
+++ b/functions/relatedcomics.php
@@ -6,7 +6,7 @@
  * Usage:  [related_comics]
  *
  */
-
+/*
 function related_comics_shortcode( $atts = '' ) {
 	extract(shortcode_atts(array(
 					'limit' => '5',
@@ -69,3 +69,4 @@ function related_comics_shortcode( $atts = '' ) {
 add_shortcode('related_comics', 'related_comics_shortcode');
 
 ?>
+*/
diff --git a/functions/relatedposts.php b/functions/relatedposts.php
index f37b629..89c136a 100644
--- a/functions/relatedposts.php
+++ b/functions/relatedposts.php
@@ -6,7 +6,7 @@
  * Usage:  [related_posts]
  *
  */
-
+/*
 
 function related_posts_shortcode( $atts = '' ) {
 	extract(shortcode_atts(array(
@@ -72,4 +72,5 @@ function related_posts_shortcode( $atts = '' ) {
 
 add_shortcode('related_posts', 'related_posts_shortcode');
 
-?>
\ No newline at end of file
+?>
+*/
diff --git a/test/ComicPressRelatedPostsTest.php b/test/ComicPressRelatedPostsTest.php
new file mode 100644
index 0000000..dab7f96
--- /dev/null
+++ b/test/ComicPressRelatedPostsTest.php
@@ -0,0 +1,40 @@
+<?php
+
+require_once('PHPUnit/Framework.php');
+require_once('MockPress/mockpress.php');
+require_once(dirname(__FILE__) . '/../classes/ComicPressRelatedPosts.inc');
+
+class ComicPressRelatedPostsTest extends PHPUnit_Framework_TestCase {
+	function setUp() {
+		_reset_wp();
+		$this->rp = new ComicPressRelatedPosts();
+	}
+
+	function testBuildPostTable() {
+		$posts = array(
+			(object)array('ID' => 1, 'post_date' => '2009-01-01', 'post_title' => 'Post 1', 'guid' => 'post-1'),
+			(object)array('ID' => 2, 'post_date' => '2009-01-02', 'post_title' => 'Post 2', 'guid' => 'post-2'),
+			(object)array('ID' => 3, 'post_date' => '2009-01-03', 'post_title' => 'Post 3', 'guid' => 'post-3'),
+		);
+
+		foreach ($posts as $post) {
+			wp_insert_post($post);
+		}
+
+		$categories = array(
+			1 => array(1),
+			2 => array(1),
+			3 => array(2),
+		);
+
+		foreach ($categories as $id => $cats) {
+			wp_set_post_categories($id, $cats);
+		}
+
+		$output = '<div class="related_posts"><span>Title</span><table class="month-table"><tr><td class="archive-date" align="right">Jan 3, 2009</td><td class="archive-title"><a title="Post 3" href="post-3">Post 3</a></td></tr></table></div>';
+
+		$this->rp->related_categories = array(2);
+
+		$this->assertEquals($output, $this->rp->build_post_table('Title', $posts));
+	}
+}