I just thought of an idea for a circuit where you can have potentiometers = ADCs x Outputs w/a single chip, and still get a reading for each individual pot! So you hook up the wipers of all the pots to one of the three ADCs (for example, w/ 8 outputs, hook up 8 pots to each ADC). Then, you connect one end of every Pot to ground, and then hook up the other end of 3 pots to each output (in a grid, each row's wipers would be connected to one ADC, and each column's ends would be connected to a single output). Then, you switch HIGH on the output for the column you want to read, and get an ADC reading for each pot! You could quickly go through with two nested For loops and store it in a matrix.