I live in Southern CA, in the city of Burbank. I used to live in a house on the street of Andover, the address of which I'll keep separate, simply because I don't live there anymore and I can't quite get their permission to disclose it.
The night before my family and I were going to move into this house (in the year 2006), my niece and I decided to have a little fun and stay at the house alone, while my parents slept the last night in our old house. To up the ante, we secretly brought an Ouija board with us, and later in the night- close to midnight- she and I pulled the Ouija board out.
It was incredibly anticlimactic. We asked if anything was there, and despite feeling spooked and like we were dabbling in things we had no business dabbling in (we were), nothing exceptional happened. There was no response, and a few minutes after repeating the question we ditched it, putting the board (carefully) away.
My niece and I were staying in the den of the house, located slightly south of dead center of the whole house. There were these shutter doors that separated the kitchen and a hallway leading from the den to the bedrooms and a living room, the windows of which were also shuttered. Shortly after the Ouija board had been put away, weird sounds started happening, like someone was walking down the hallway. The doors in the den started slipping open despite having been locked, and things began progressing through the night. In no time at all we could hear the window shutters slamming open, and lights were flickering in the kitchen. My niece and I, I am proud to say, simply weathered most of the experience playing music quite loudly and staying relatively relaxed.
At one point, my niece had to use the bathroom. She begged me to come with her, so I did so, feeling nervous because there were no lights set up in my parent's room- the room we went through to get to a closer bathroom (that didn't require us to walk through the hallway).
After a few minutes, the light flicked off in the bathroom, and my niece angrily asked me why I'd turned it off, and that it wasn't funny. I hadn't, of course, despite there being a light switch both inside the bathroom and outside; after several seconds of her flipping her switch, I began flipping my switch, but to no avail; the light refused to come back on.
At that point, I heard something like a scream coming straight from where my room was going to be, and I started freaking out a little more. My niece swears she didn't hear it, so my freaked out mind may have supplemented that one, but I was incredibly sure that I'd heard it. My room was also connected to the room we were in by a sliding door, which I very quickly shut.
After that, we called my parents and begged them to come sleep with us, during which time the activity ground to a near halt.
For days after we fully moved in, weird things kept happening; our things would disappear, boxes would move when only my niece and I were watching, and the lights would continually break or refuse to work. My mother eventually got shoved off of a stepladder that she'd been standing on, and I finally realized that we had to take matters into our own hands. Clearly we'd called something and it was our fault, so we had to fix it.
I'm relatively spiritual. At this point in time I believe I'd been doing Tarot card readings for several years (despite being in High School), and I was always relatively spiritually open. I'd read somewhere that sometimes, spirits are angry because you don't know who they are. So I took my niece and we stood in front of a fireplace, quietly saying (to some affect) into the open air "We realize that we brought you into this world, and we know that it's our fault. We'd like to make you a part of the family, and though we don't know who you are, we'd like to offer you a name, if you'll take it." Both she and I had previously decided on the name Beethoven, which we both said at the same time (through practice).
Almost immediately after, all activity stopped. Every now and then we'd feel like something else was there, but it was no longer malevolent; the exercise had worked (thank God, because I didn't have any other tricks up my sleeve).
You'd think it ends here, but it doesn't.
My mother became friends with one of our neighbors, who began nervously asking if we'd experienced anything... Weird... In the house. When Mariah (my niece) and I asked her why, she said that the family living before us (immediately before us) had had... Complications.
The husband had been cheating on his wife- a woman named Dhana- with her best friend. Crushed and hoping to somehow fix their broken marriage, Dhana got pregnant with I believe their fourth child- which ultimately killed her. Neither she nor the baby made it through birth.
Immediately, Mariah and I knew that that was our "Beethoven". However, nothing bad was happening anymore, and if anything Dhana (Beethoven) had become a familiar feeling and part of the family. The story faded from our minds.
Four years later (2010), I threw a Halloween party. I had just graduated from High School and I was the master of scary stories and experiences, and we pulled out the Ouija board again, just for fun (because clearly I hadn't learned my lesson). It worked! We got several ghosts with clear answers, which obviously means one of my friends was pulling the strings on it. There were about five of us playing, including my niece, Mariah.
After a while of laughter and fun, the air seemed to change, and everyone got really quiet. My mom was watching from above, and we were all playing. It was weird; the whole atmosphere changed, without any of us consciously noticing until much later. The dial on the board was suddenly shaky when responding to our familiar question, "Is anyone there?" and slowly dragged its way to Yes. All of us noticed that things were immediately different from before. I really remember this, if simply because I've told the story so many times. Everyone was paying extreme attention, sitting as still as we could.
When we asked "What is your name?" the dial slid to the letter "D".
I'm sure you can see where this is going. The dial on the board continued- much to my horror and my mother's growing discomfort- to spell out "Dhana".
I wanted to stop right then, but everyone was curious to my sudden change in attitude. I hadn't shared Dhana's story with anyone since learning it, because it wasn't too big a deal. Nothing terribly scary. If anything, I'd mentioned Beethoven's introduction, but never explained the link between our family ghost and the poor woman who'd lived there before. My friends convinced me to keep going, and we learned that she had a very dark intent; Dhana was furious at the loss of her baby, and that her husband hadn't even stuck around to grieve. This board was explaining things I hadn't even explained just then; how the guy had left immediately after her death to move in with his illicit lover.
It was chilling, and it was getting darker by the minute. At one point, I noticed the dial doing something erratic, like it couldn't decide; it was then that I realized that it was trying to go in circles, and when that proved too difficult for the angry ghost, it started going backwards from 0 to 1.
For people who don't know, that's how a ghost opens a portal to the real world, to come through as a far more malevolent being, possibly no longer site-bound. I immediately stood up, grabbed the dial, and threw it across the garage, putting the whole thing away.
My friends were upset that I'd done such a thing, effectively ruining their fun, but I'd had enough. That was the end to my Ouija expeditions.
The energy of the house never really changed, though the air maybe got a little stuffier. My family fought a little more often, but otherwise, nothing terribly awful. Beethoven was still a mildly benevolent spirit in the house.
However, shortly after moving out of the house, our neighbor (the same from before) called us up. She said that while outside, she'd seen a long black car pull up in front of the house, and a Priest walk out of it and into the home. After a couple of hours, he had left, and to this day he hasn't returned. I can only assume that Dhana was, sadly, exorcized from the property.
I haven't felt any other experiences that match Beethoven. It was probably the closest I've ever gotten to a truly dangerous spirit.