Now I finally understand the module pattern.  Also, "use strict."
Handle post not found with a 404 from the similar_posts method
I'll be damned if I'm going to render this in both HTML and JS.
Finally handle invalid post URLs
Define exception heirarchy so that we can handle these things in such circumstances.
Load the posts!  Also provide an error message if no matches found.
Show the spinner until it's complete.  Add logic for showing a summary of the results and actually displaying it in an IFRAME!
Start of caching in controller for the heavy lifting
Cache expiration is now hard coded in Post
Styling for results.  Make results reachable by JS using IDs
Forgot to add all the caching db stuff