--- a/app/models/post.rb
+++ b/app/models/post.rb
@@ -17,6 +17,10 @@ class Post < ActiveRecord::Base
     end
   end
 
+  def related_posts
+    Post.search(:limit => 4, :conditions => {:tag_list => tag_list.join("|")}).reject {|x| x == self }.first(3)
+  end
+
   before_validation :generate_slug
   before_validation :set_dates
   before_save :apply_filter

--- a/app/views/posts/show.html.erb
+++ b/app/views/posts/show.html.erb
@@ -13,6 +13,18 @@
   </li>
   <% end -%>
 </ol>    
+<div class="related">
+  <% if @post.related_posts.empty? -%>
+    <p>Hungry for more? Head on over to the <%= link_to("archives", archives_path) %>.</p>
+  <% else -%>
+    <p>Hungry for more? Try these <strong>related posts</strong>, or find more in the <%= link_to("archives", archives_path) %>.</p>
+    <ul>
+      <% @post.related_posts.each do |post| -%>
+        <li><%= link_to(h(post.title), post_path(post)) %></li>
+      <% end -%>  
+    </ul>  
+  <% end -%>  
+</div>
 <h2>Post a comment</h2>
   <% unless @comment.errors.empty? -%>
   <div class="errors">

--- a/public/stylesheets/rhnh-standard.css
+++ b/public/stylesheets/rhnh-standard.css
@@ -433,6 +433,23 @@ hr
   overflow: auto;
 }
 
+/* Post */
+
+.related {
+  background-color: #f8f8f8;
+  border: 1px solid silver;
+  padding: 5px;
+  padding-left: 10px;
+} 
+
+.related ul, .related p {
+  margin: 0px;
+  padding: 0px;
+}
+
+.related ul {
+  margin-left: 15px;
+}
 
 /* Syntax */
 

--- a/spec/models/post_spec.rb
+++ b/spec/models/post_spec.rb
@@ -151,6 +151,18 @@ describe Post, '#denormalize_comments_count!' do
   end
 end
 
+describe Post, '#related_posts' do
+  it 'returns first 3 related posts, excluding the post' do
+    post = Post.new
+    post.stub!(:tags).and_return([
+      mock_model(Tag, :name => 'robot'),
+      mock_model(Tag, :name => 'heart')
+    ])
+    Post.should_receive(:search).with(:limit => 4, :conditions => {:tag_list => 'robot|heart'}).and_return([post, 1, 2, 3, 4]) 
+    post.related_posts.should == [1, 2, 3]
+  end
+end
+
 describe Post, 'validations' do
   def valid_post_attributes
     {

--- a/spec/views/posts/show.html.erb_spec.rb
+++ b/spec/views/posts/show.html.erb_spec.rb
@@ -22,7 +22,12 @@ describe "/posts/show.html.erb" do
       :published_at      => 1.year.ago,
       :slug              => 'a-post',
       :approved_comments => [mock_comment],
-      :tags              => [mock_tag]
+      :tags              => [mock_tag],
+      :related_posts     => [mock_model(Post, 
+        :title        => 'Hello',
+        :slug         => 'hello',
+        :published_at => 1.year.ago.utc
+      )]
     )
     assigns[:post]    = @post
     assigns[:comment] = Comment.new