thanks for posting that jimbo ... I've been wanting to do something along those lines for several years now - but on a much smaller (one tabletop) scale ... my official excuse is to use it for "PLC training" classes - but to tell the truth it looks like just plain fun to do ...
the problem: the last time I checked, the controllers all HAD to be Lego brand ... has anyone heard of being able to modify the inputs and outputs for use with standard PLC hardware? ... if so, my Christmas wish list just got a whole lot longer ...