A research group at Tokyo Institute of Technology is developing a device called the Haptic Adapter. This is a new type of user interface, which gives a tactile sensation to touchscreen operation when using devices such as the Nintendo DS and iPad.
The adapters comes in two models, one in the shape of a ball and the other resembling a brush. With the ball-shaped haptic adapter, the user can experience the feeling of using an analog joystick on the touchscreen. With the brush-shaped haptic adapter, the user can experience the feeling of clicking.