Pack rendered images into .blend? I have a problem: I render images, and if Blender accidentally quits while performing some sort of operation, I lose my rendered data. (If only a single unsaved image).

I have external data > 'Pack all into .blend' enabled, but this does not pack rendered images into the file. 

Is there a way to pack single rendered images into the .blend along with all of my already packed textures?

This would be extremely helpful, and would save a lot of render time!
If I am correct, you want to automatically save the rendered result so if Blender crashes you have the last known output.  Using composition you can save the output as follows:



This image, by default, will be called Image0001.png in your chosen path. If you really really really wanted to pack it in the Blender file I suppose you could create a non-rendered object that takes that image and then it should also be stored (not tested). However, I think just the automatic saving is probably what you are after.