Right, but with a shared bus, how would a shield know that 0x80, 0x100, was meant for shield 1, not 2 and 3.... this wold require a protocol correct?
Again, my newbness might be showing, but the idea of jumpers(or wires) solves the problem, and does not create any new ones... I'm not sure about I2C. Can you elaborate on I2C?