According to T-shirt slogans everywhere, you're not paranoid if they really are out to get you. That said, we're reactivating our alarm system at home for the first time since we moved in. We've had two burglaries in the last week within 150' of our front door, and we're understandably nervous. We don't have nice stuff, but a burglar wouldn't know that until the damage was done. So we're embracing some necessary paranoia. I don't like the thought that an alarm system is a mandatory part of life in our neighborhood now, but we're getting in the habit of turning it on at night and whenever we leave the house. It's better than the low-grade dread I had been getting whenever I left the house; I was a low grade of constantly anxious that I'd come home to find the door glass smashed in, cats kicked around, and important stuff missing. The alarm system helps a bit with the anxiety.
The fact that the house had an alarm system was a real bonus when be bought it; we didn't find out until we moved in that the seller didn't know any of the codes for the system. In 2000, this was problematical. The alarm installer had gone out of business, and another company would gladly sell us a new system, or reinitialize the old one for a few hundred dollars. So I unplugged it and pulled the battery and it sat unused until this week. I'm still a bit amazed by technology these days; what was an insurmountable problem ten years ago, took me an hour with Google to resolve. That proprietary programming and set-up guide nobody had on hand or was willing to share: available for free on at least eight different websites in pdf format. The top-secret method for resetting the installer code, even after the original installer specifically locked out the reset feature: freely available in a five-year-old archived bulletin board discussion among alarm installers. We're living in the future, in a lot of ways I regularly take for granted, but I was amazed by the ease of solving a problem that wasn't really solvable ten years ago.
So I replaced the backup battery (which had died in ten unused years), reprogrammed the system myself from scratch after a hard reset, and reconnected the phone line to the autodialer. We've now got a fully functional alarm system. I've got new cat-proof motion sensors on order; in the meantime, the old ones are set at an angle such that a cat on the sofa won't set them off, but anyone coming in through a window will. I've got an unused zone, as well, so I'm thinking about adding a glass-breakage detector. This is still something the cats can set off accidentally, but I can work around this by removing all breakable cat-level glass from the entire house. Or maybe I'll just depend on the motion sensors.
As soon as I had finished programming and testing the alarm system, a neighbor dropped by and told me she had locked her keys in their detached garage, and couldn't get in the house or back in the garage. I went over to pick the lock on her garage door and let her in, and I made sure I locked the house and turned on the alarm system when I left. The universe seems to strongly prefer irony, and the most ironic possible moment for a break-in would be immediately after I installed an alarm, but didn't turn it on, while I was breaking in to someone else's place....