Build your own fake car-alarm flashing led.
The circuit is powered by 9V battery and is interupted by a Switched live wire (14.2V).
The two LEDs on the right actually represent a red-green-bicolor LED.
If the switch on top is open, the LED blinks red, indicating the "alarm" is on. Closing the switch - turning the ignition key - makes the LED switch to green...
