Ps2 Rocker breakout board
example code and circuit : http://rca.tiddlyspace.com/Joystick on our version sw is most likely digital switch
and vr x and vr y are analog inputs.
Laser http://pyevolve.sourceforge.net/wordpress/?p=2383 -be careful
https://code.google.com/p/arduino-new-ping/ Ultrasonic Distance Sensor -Library and sample circuit
Many more samples and code here: http://linksprite.com/wiki/index.php5?title=Advanced_Sensors_Kit_for_Arduino
Magnetic detection switch
speakers
Shock Sensor Module KY002:
Obstacle Avoidance KYO32
Obstacle avoidance sensor module KY-032 for Arduino: With 4 pins, use an infrared beam to detect proximity of obstacles. The potentiometers can be used to adjust sensitivity. Pin 1 is Ground, pin 2 is 5V power, pin 3 is digital output (on/off depending on the beam), 4 is enabling.
Magic Cup