@liudr
That is an awesome shield! A lot of things going on on that one! I just gave you another good Karma for that one.
You should sell that one on Ebay, for sure.
By the way, thanks for your advice, but you should know that I am one of those one who really read datasheets and always have a calculator on my left 
I really take the extra job of modifying boards.
@mrquesito
That is exactly what I was thinking off !
Can you share a simple example?