I have a dog. He's not a biter, but he has a piercing bark.
I have good neighbors and we watch each other's homes. Last year, when the two rescue pits got into a fight, I was screaming for help in the back yard, and not long after, a sheriff's unit pulled up in my driveway because one of my neighbors had called them. The neighbors weren't going to bust into the middle of a dog fight, and I don't blame them, but they did call 911.
I don't have a gun but am in the market for one as soon as I have the money to afford one. But when people offering "free" alarm systems come to my door (yes, I've had that scam happen more than once), I tell them that my home security system is a pit bull and a shotgun. Enough of them have seen the pit bulls in the house (Eddie and Leonard before, and now Dexter), that they apparently believed the part about the shotgun, and I haven't' gotten any more of those "offers."
The car alarm on the nightstand bit is iffy, according to Snopes. People are so used to hearing car alarms go off that they don't pay any attention to them anymore. It's also iffy that your key switch would have the range to set off your panic button from inside the house. It depends on how close your car is to your bedroom and the thickness and composition of your outside walls.
Edited by Phoenyx - 7/31/12 at 2:53pm