Rename asset file upon upload? Is there any way to rename files upon there upload to an assets field? 

I know I can hit the options of the file and rename manually, but was wondering if there was a way to do this automatically? i.e. renamed based on the entry ID.
Craft has the ability to dynamically add subfolder paths to Assets when you are creating the Asset field in the control panel. 

Tags like {slug} and {author.username} are some of the available options for creating the directories.

I know it has been brought up before and they have acknowledged the possibility. So who knows, maybe we will see it in 2.2? 

For now, if organization is a concern I recommend using subfolders to keep it clean.