The Arduboy platform is heading for kickstarter. It is a creditcard shaped gaming platform featuring capacitive buttons, a small OLED screen, speakers, battery and a barebone Arduino (atmega).
I think that this looks great for gaming, but can think of a gazillion more applications. Just having access to a really low cost, customizable interface like this can revolutionize user interfaces to many low end embedded projects.
Via boing-boing.