I have the same issue with a set of sites I inherited, so I'm anxious to see what the other Monks have to say about this. One thing I have been contemplating is moving from MySQL to PostgreSQL, modeling the database correctly, then using updateable views to mimic the old database structure. I'm not suggesting that as a course of action for you, but wouldn't mind a few comments on this approach from other Monks. I'm also contemplating ORM as a solution.