So SharedObjects are stored locally in readable text form, is there any way to store these in a more secure form (hashing?).
When a user's maximum SharedObject capacity is reached, what happens to a new SharedObject? Is it discarded, or does it overwrite existing sharedObjects?
sharedobjects are not readable in text file editors and you cannot control the format in which they are stored. you can do whatever you like in flash to encrypt the data before it's stored but it makes no sense to try and secure the data.
when storage is exceded sharedobjects are deleted. the oldest, i believe, are deleted first.