Just like to share my multimux...
It's 4 slave 4051Bs on top of a 4051B master which is on top of a 74HC595 shifter. Its about 1" high and gives me 32 analog inputs for the cost of three pins on the Arduino to contol it and one analog for the input. A soldering nightmare as there is no space between the chips. I needed a multimux solution for inputs and just noticed how many of the pins simply 'overlapped' and couldn't resist building it.
It will take another 4 slave 4051Bs on top without needing any further master muxes or shifters... that's 64 analogue inputs for three pins... meltdown ahead I fear
By the way I'm sure there are better ways but what the heck.