Note: I am using SDL Tridion 2011 SP1.
I have created a schema with a multi-value embedded schema. The embedded schema contains 2 fields:
component - a component link (any schema allowed) component_template - a list of allowed component templates for the selected component
What I want to do is use the selected component to determine the allowed component templates and expose a list of allowed templates for selection as a drop-down list for component_template.
This replicates the functionality of a component presentation list on a page but within a component.