Well this is only a idea and im sure many ideas like it have come up here. Correct me if im wrong but avatars are partly saved on a memory unit "HDD" , "MU" If this be the case couldent a shader or tiff exploit be made ? if it was to work of course what would it give access to ?
Any how im just throwing my idea out.

I doubt they'd save the entire model or even the graphics to HDD. an avatar save basically needs to consist of this (simplified):

01020105...

"face 01, nose shape 02, mouth shape 01, hair style 05"..


so it only needs to take a few bytes of space.

well maybe not the entire model but something that could trigger a small peice of code allowing us to do what ever. Course i know it wouldent be that simple.

if the avatar graphic was not saved onto the hdd i would not be able to play offline and have an avatar so destroys you theory