I do believe in the paranormal, but I haven't seen anything scary like that, at least since I was younger. I have been in many places where people tell they have seen paranormal stuff, but personally I haven't seen anything there lately. It's a bit of a bummer because it's like ghosts hide from me, instead of it being otherwise.
But when I was a kid, I did have a few weird experiences. I remember once seeing a man floating from one side of a hallway to the other, emphasis on floating, because there was no floor there. I didn't think much of it or felt scared, I was just like, "oh look, a ghost". And another time, I was in my grandparents' room, where out of the corner of my eye I see what looks like a little girl but when I turn to see, there's no one there. Needless to say, there were no little girls at that moment at my grandparents' house.
But the one time I've been the most scared in my life, was one day after a huge fight there at my grandparents' house. There was a fight with my aunt who was staying there, and things got really bad. So a while after that, I woke up at midnight to go to the bathroom, and as I walked there, I walked by the room where my aunt was sleeping, and, I kid you not, I clearly saw a huge shadow lingering above her bed. It was a human-like figure, but it had horns on its head. I didn't want to jump to conclusions but I'm definitely sure of what I saw. My blood ran cold and I was absolutely freaked out, but luckily, I haven't seen anything like that ever since.
And well, those were my scariest experiences with ghosts. It seems very rare for me to experience anything like that but I'm definitely not closed to the possibility of seeing something again... even if it scares the everloving poop out of me!