http://www.fotokatie.com/katier/?p=170
Computer controlled permutative switching of circuits (allows for 16 points to be connected) using 3 bits (serial data transmission) over USB or parallel port. Modular design of 2 serial/parallel boards (74HC595 shift register chips see: http://computerchristmas.com/index.phtml?link=how_to&:=25) and 4 switch boards (4016/4066 quad bilateral switches): http://www.doctronics.co.uk/4016.htm. Switching points are also exposed to CV (control voltage).