Is there a way to attach an AMI, or a copy thereof, to an instance? This would be a non-pay public Linux AMI. An example would be the Ubuntu 12.04 LTS AMI. But I don't want to be limited to just that one, either (so a copy of it elsewhere, while nice to know, isn't the answer). In particular, what I am trying to avoid is making a copy that is running or has been run.
The test would then be to make a snapshot of that, and register that as an AMI, and it would be an exact copy. My intention would be to modify the copy (as my own volume). But my modifications would not work if it is a root device initially (since the transition of changes would cause a crash).