title: Setting up Rails routes based on QueryString
body: <p>I've seen similar questions on this, but not quite what I'm looking for...
  Forgetting for a moment the <em>wisdom</em> of doing this, is it <em>possible</em> to do this?...</p>
  
  <pre><code>/object/update/123?o=section    # ==&gt; route to SectionController#update
  /object/update/456?o=question   # ==&gt; route to QuestionController#update
  </code></pre>
  
  <p>...and if so, how would that be done?</p>