title: Graphically represent relations between objects (not classes!) in Rails?
body: <p>I have two classes in one of my Rails apps that have a many-to-many relationship.  I'm trying to tidy them up (ie delete a bunch and move a bunch more) and it would be great if I could actually see how they link up.  (I can print out a text file listing each instance of class A and then list it's associated class B objects under it, but this isn't quite hitting the spot.)  </p>
  
  <p>In the past, I've used gems (like <a href="http://rails-erd.rubyforge.org/gallery.html" rel="nofollow">http://rails-erd.rubyforge.org/gallery.html</a>) which do this for <strong>classes</strong>, ie they build an entity-relationship diagram <code>.dot</code> file.  Now I want to do it for <strong>instances</strong> of two classes.  Has anyone seen anything like this?</p>