I have 2 front doors, but there are windows next to both so I can see who is out there. I would probably be armed if I got a knock in the middle of the night.
We live in the middle of our block, in a suburban neighborhood. If someone knocked on the door that late at night, I would assume it was a neighbor in need of help or something and go to the door. Of course, the first thing that would happen, would be that the dogs would go crazy barking. That should be enough to scare off most people who don’t know us. I would look out the peep hole and if it was someone I knew, probably open the door and find out what’s going on. If I didn’t know the person, I might call out and ask them if I could call the police for them, but I would not open the door. My dogs bark like dogs from hell when the door is shut, but as soon as it’s open they’re all, “pet me, love me”.
If someone knocks on my front door, and I don’t feel safe opening it because I don’t know who it is or whatever, I will sometimes go out the back door and walk around to the front and talk to them out there. They could still get me, but at least they have to do it out in the open where the neighbors could see. At midnight, though, they’d not even get that- although I might yell through the door to see who it is.
Yep, me three.
I live in a tiny apartment building (4 apartments), and my neighbors do occasionally keep odd hours. I’d just assume it was someone who got the wrong door and just ignore it, or if it persisted, I might call out to ask who they were looking for and redirect them.
Not really related, but yesterday morning as I was leaving, the door to the apartment downstairs slowly opened (it opens directly onto the front stoop, so is outside and in full view of the entire street). I thought it might be someone trying to catch me to ask me something, so I stopped and called out “hello”. My neighbor’s two-year old son stepped out onto the front step, competely naked, and stood there staring at me. His mother quickly scooped him up and apologized.
This is something that’s always puzzled me. If you’re home alone, why not just, y’know, go ahead and lock the door? 
It’s not like you get some Good Citizen Merit Badge for leaving the door unlocked…
I don’t know, just never got in the habit. I’m in and out of the house probably 20 times a day, often with my hands full. I’ve never once in my life had a problem due to not locking the doors.
We live in the sticks. I’d probably think it was some kids that got stuck in the ditch… but with everyone having cell phones now, I don’t know.
The dogs would be going crazy. I’d turn on the outside lights, and see who it was. I may have a pistol with me.
As the IRA reminded Margaret Thatcher, the bad guys only have to be lucky once. You have to be lucky every time. James Michael Loren used to walk around and try unopened doors. He walked into a house on 31st with three people asleep and assaulted one. They’d left the door unlocked. Esme, we’re not sure about.
I wouldn’t call anyone, but I wouldn’t say anything either. If they persisted in knocking, I’d probably call 911. (311 automatically transfers to 911 after 6 o’clock)
If I did have to knock on someone’s door at an unusual hour, I’d knock AND call out my name. “It’s BeeGee” Why make someone panic if you don’t have to.
If you do ask who’s there, make sure you do it in a forceful, unwavering voice. Show no fear and a little bit of “are you nuts?”.
Guess I’m just not a worrier. 
One apartment I lived in in college was a studio with a door on the outside of the building. All the other apartments in the building were accessible through the inside of the building. I wound up having to keep my door locked while I was home or I would have random strangers barging in, thinking my apartment door was the door into the building.
About a month ago my sister-in-law, who lives in Colorado Springs, was awakened by someone banging on her front door, then sounding like they were trying to break the door down. She called 911 and they sent someone out to check. Apparently it was an Air Force officer new to town who had been out drinking with his buddies and forgot where lived, and was trying to get into the wrong house. The cops told her they get about one of those every week.
Last time I had a middle of the night knock I could tell it was a real emergency – I could see their car lights in the next field door: one above the other! My fault for having a light on that hour. Just a father and son out on a drunk. With some apprehension I drove them home (5 miles).
field next door
In my former house, I had a front bedroom window above the front door. I couldn’t directly see it because of the shape of the front entry way, but I do recall on at least one occasion throwing open the window and yelling “What do you want?”. They made excuses and I told them to fuck right off.
In my apartment, I would stumble around getting dressed, then go over near the front door and pause to listen for someone outside the door. If I didn’t hear anyone, I’d go back to bed. My neighbors are sometimes assholes, or have guests who are assholes and it isn’t unheard of for someone to knock on the door as they go past. One of their guests did this about 9pm just the other day.
It’s actually not as strange a mistake to make as it sounds in my building either: All the other apartment doors on my floor are inside a corridor, with mine the only one outside the corridor and close to the main door to the building. Still, everyone else seems to figure it out fine, except that one dude.
I’d probably wake my wife up and have her ready to flee with the kid, I’d grab the pistol and chamber a round, but decock it (making the trigger pull longer and harder for safety), look through the peephole, and if I didn’t recognize the person or see that it was someone like a cop or fireman, probably talk to them through the closed and locked door.
I have some aggressive sounding dogs, so I would hope any middle-of-the-night knockers would change their mind upon hearing them. I probably wouldn’t answer unless I could clearly see something was wrong with the person, arm was falling off, she was hold her leg, etc. I don’t know, I’d have to assess that situation.
This, more or less. The road I live in is narrow, winding, and unlit and has ditches and field on either side of it. This time of year, anyone who runs off it at midnight is definitely going to need help before morning. I’d be none too cheerful about it, but I’m pretty sure I’d answer the door.
Y’know, that’s actually a good question. Lemme give it a try. I likewise lived, alone, in the middle of nowhere for a few years, and it was the most bestest goodest nicest place I think I ever lived. ( Photo. )
I never locked the door. Not by day, not by night, not when I was there, not when I was out at work all day. (Except I locked it when I went on a several-day vacation.) Perhaps because the security was so flimsy (note the flimsy windows) that it couldn’t have made much difference. But neither did I ever lock my car when I was there, nor when I was in the small town down the hill. I did lock my car when I was at work, down several hills away in the Medium-Smallish City.
There was always something of an exhilarating sensation of simply being in a place where I felt secure enough to do that. Not at all like the constant sense of paranoia of living in a Medium-Large (or larger) city, as I do now. Yuck. The only unexpected visitors I ever saw in the vicinity were occasional guests of the landlord who occasionally wandered by (during the day) and occasional visitations by the horse from a neighboring property.
I did refrain, however, from wandering about the property after dark. It’s dark out there! Not to mention the known presence of our resident mountain lion in the neighborhood.
Zyanthia, did you ever find out who it was?