Adobe TV has posted my final Flex in a Week video. This one is on the use of Flash graphics objects in Flex applications, covering both drawing directly into the Graphics object for custom rendering in your updateDisplayList() method as well as creating and adding Flash shapes to your components. (Note that you have to have a completely cusom component, subclassing UIComponent, in order to add non-component children such as DisplayObjects or Sprites to the child list of your component; other Flex components only understand Flex component children).
It's not terribly advanced, but is meant more as an introduction to some of the graphics basics, including Flash's use of retained mode rendering and why you always need to clear() the graphics display list.
The source code for both examples is available here.