I don't want to sound morbid, or like a killer, or crazy. But is there some literature on anti-personnel traps? I don't mean using explosives either. Your basic snares, trip lines etc for perimeter defense. I would imagine it would come in handy if things got so bad that you had to box yourself into your home.
After your neighbors starve or leave and you and your family are alone or one of the last in the area, eventually roaming bands of people will show up. Either hostile or friendly.
I am serious about this. Personally I would post signs warning that no mercy will be given to trespassers but with a way for friendlies to alert us of their presence for bartering / trade. (of course supposed friendlies could really be hostile)
Probably not a good idea, but I hear what you are saying, I'll try to comment as controversy free as possible, and with respect to kev and board policy.
You can't CREATE a danger with snares, etc., even on your own property. Plus, they would be a hassle to maintain AND concentrate on day-to-day living, loved ones wandering into them, etc. If you want something dynamic, there are commercially available, battery-operated alarm signals that you attach on the door and the jamb, and when the door is opened it pulls a pin and makes a loud noise until you put the pin back in. Great for doors and windows.
However, a barbed-wire fence around a car lot is a perfectly legal way to protect their interests, and is effective because the open presence makes one think it isn't worth the hassle. So historically, barbed-wire fences are used to keep things in...and out.
Following the aforementioned logic of static perimeter defense, what protected a perimeter before barbed-wire? You can look to medieval history to answer that question. Again, mantraps are illegal. However, calling on the example of the barbed-wire fence it seems that it is legal if the danger is pointed straight up, not out.
Also, there is the perimeter of your home, of your yard, and of your street. You can find the Army field manual for Countermobility. This the application of roadblocks using bollards, logs, and other debris to slow down cars and people. You in your home against the world aren't such great odds, however you and your neighbors against the world, the odds are better if only slightly. I find muffin baskets are a wonderful icebreaker to transition to the topic of post-apocalyptic neighborhood watch programs.
What to do in a SHTF scenario? Maybe pile up as much debris as possible around windows in order to create specific access points. Great for onesy-twosy looters, but there isn't much you can do to protect yourself from overwhelming numbers of desperate people.
Ultimately, do you want to look like you have something to protect?
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