The Object List Builder Field Type, which was introduced with ADF v1.8.1, provides an interface to construct a free-form text field using the Rich Text Editor and to include custom element data from a bound custom element.
This allows for authoring of rich content that references records contained in a custom element. The cool thing about it is that all the references are automatically when the core custom element record is modified. That way you don't have to go back to into the RTE to change the content.
For example, on a higher education site, if you were building curriculum requirements for a degree program, you can simply drag and drop courses from the courses tab into the Rich Text Editor. Instead of the course name being hard coded into the RTE, just the course's ID is saved and then dynamically replaced at page build time. This allows for the rendering of the item to also be configurable.
See the screenshot below for an example.