If you love RC cars and iOS devices, how about combining the two with a Dexim Monster Truck that can be controlled by your iPhone, iPad or iPod Touch. Using the included transmitter and the free AppSpeed app, move the truck either by using the on-screen touch controls or use the device's accelerometer. The car can be moved by tipping your iPhone forwards, backwards or sideways.
The Gadgeteer, Dexim Announces New AppSpeed iOS-controlled Vehicle
