Extra Input/Output pins

We can use to trigger 8 outputs with the use of 3 pins with the 74HC595 IC. And read/write 8 inputs/outputs with the 74HC4051 IC but only can read/write 1 pin at a time. Does anyone know what IC can read/write 8 inputs/outputs (analog and/or digital) at the same time?

Check the dataport commando's - http://www.arduino.cc/en/Reference/PortManipulation -

or something like - http://www.sparkfun.com/products/8130 -

Any cheaper ones?

$1.50 for 8 pins = ~20 cent per pin (uses 3 pins to control eight pins, but note that these can be chained ...)

This is also interesting - http://macetech.com/store/index.php?main_page=product_info&cPath=4&products_id=23 - maybe too price but a lot of pins

64 IO pins for $25 is ~40 cent per pin

The I2C I mentioned is 16 pins for $12 = 75 cent per pin (you are right, not really cheap, but they use only 2 pins as they are on the I2C bus)