Form with relations
Since version 1.1 of ConfiForms plugin in ConfiForms Field Definition macro you can use one new field type, called Smart Dropdown.
This field type allows you to reference data from other ConfiForms forms. You can reference both: form fields data, such as choices from dropdown fields or the data stored by other form. So, basically you can create forms with data classifiers and reference them from your form. See our I love databases recipe to learn more.
Basically you can reference any field, with an exception of other Smart Dropdowns. Your data is dynamic and changes when the original field changes.