https://vine.co/v/hwYQh9hWnOV

Combination of led with light sensor, mixed with a reader on/off switch, creates a low-tech bar code reader with sound.

Develop a reaction for two or more sensors that utilize the sound, buzzer or LEDs as a response. You can choose between the button, the light sensor, the temperature sensor or the “touch sensor” described at http://lilypadarduino.org/?page_id=552. The sensors do not need to be integrated with each other.