As you all probably know, Doctrine has been tightly integrated with a few different PHP frameworks. Since symfony was my choice of framework a few years back, I have dedicated a lot of time towards working on the integration between the two.
Something I've always thought would be fun to build and has been one of the most requested items by users is a nice web based interface for managing your schema and generate your models from it. With the new form framework as of symfony 1.1 , you can build rich forms with a nice OOP interface. This made it extremely easy to make the schema manager feature of the sfDoctrineManagerPlugin. It was as simple as automatically generating a set of forms from the schema information data structure inside of Doctrine.
This symfony plugin allows you to manage all your schema information from a nice web based interface. You can create new schemas or load your existing schemas to edit. More information about it as well as screen shots can be found here.