IOIO for Android - SparkFun Electronics. Also an interesting project, a friend pointed me to it today: an IO board for Android smartphones. It simply plugs in via USB and is accessed through a simple Java library. It has various analog and digital inputs and outputs, I2C and other goodies. You can even get a Bluetooth kit for it if you don't want to communicate via radio. Pricier perhaps than what you're used to in the Arduino environment, but still, sounds cool. I'll wait for my Smartduino first, though, which also has Android support.