A Tip every one should know:

Put your car keys beside your bed at night. If you hear a noise outside your home or someone trying to get in your house, just press the panic button for your car. The alarm will be set off, and the horn will continue to sound until either you turn it off or the car battery dies.

This tip came from a neighborhood watch coordinator. AND IT WORKS. Next time you come home for the night and you start to put your keys away, think of this: It's a security alarm system that you probably already have and requires no installation. Just press the panic alarm on your car key chain.

 TEST IT! It will go off from most everywhere inside your house whether you park in your car in the driveway or garage. If your car alarm goes off when someone is trying to break in your house, odds are the burglar or rapist won't stick around. After a few seconds all the neighbors will be looking out their windows to see who is out there and sure enough the criminal won't want that. Try yours to make sure it works before you rely on it. Just know that you must press the alarm button again to turn it off. And remember to carry your keys while walking to your car in a parking lot. The alarm can work the same way there.