About a year ago, I picked up Scott Ambler's Refactoring Databases: Evolutionary Database Design. I was won over to the idea that just as you can develop your code with TDD, you probably should be covering your databases with unit tests (at least) or even writing database tests before you make a change to the schema so you do database work in a TDD style as well.
I really like the idea, and I have been doing this (OK, sometimes I do it) by hand for a while now, just writing regular unit tests that happen to connect to the database and check its structure against a given schema file. But I haven't found any good database change management tool-kits that might help automate this process. Does anyone know any?