Changing sections displayed in each module

Changing sections displayed in each module

Is it possible to change the sections displayed in a module? For example, I have created a link between cases and sales orders. In the cases module, I would like to see all of the associated sales orders, and vice-versa. I know I can create a custom field with a lookup, but that is a manual process, and provides only a one-to-one relationship. I would like to be able to produce multiple sales orders for a case and see the linked sales orders in the case module.