I couldn't find this with Google Live Search but ScottW hooked me up.  If you want to show related or similar posts in your posts in Graffiti, just add this script to your post.view file (which, amazingly enough, you can do via the admin tool without FTPing any files to your blog - how cool is that?).

#set($similarPosts = $data.SimilarSearch($post.Id,3)) #foreach($sp in $similarPosts)

#beforeall

<h3>Similar Posts</h3>

<ol id="similarPosts" class="list">

#each

<li><a href="$sp.Url">$sp.Title</a></li>

#afterall

</ol>

#end

In theory, at the bottom of this post, you now see a Similar Posts section...  I'm not 100% sure what magic it uses to determine that a post is "similar" - we'll just have to see.