Couple of observations:

- Depending on how different "movies" and "documentaries" are, you may want to consider single-table inheritance--i.e., putting both in one table with a "type" column...

pty's improvement is a good one!

The only nit I have with it is that I wouldn't put the banner method in the controller, since it has nothing to do with the "traffic cop" jobs that controllers...

Since you're working with a MySQL database that's already full of data, do they follow Rails conventions? I.e., are the table names plural (e.g., the table corresponding to the Stock model should be...