Multiple Arduino Uno Slaves I am working on an Arduino project where I need more digital and analofgpins than the Uno offers. I was wondering how to hook up multiple Arduinos (4) together so I can use their digital and analog pins. Thanks in advance.
I suggest using a single Arduino Mega.  It offers 54 digital I/O and 16 analogue inputs.

I suppose you could also use I2C or SPI to communicate between multiple Uno's.