I can't say I have been standing in front of a ghost, but I have had experiences of ghosts and poltergeists in the past.
I remember not too long after I had my first child, I was lying in bed, and it was really late at night, and I could hear a little girl shouting for her mum. Thinking it could be a child lost outside on the street, I went to check, and there was nothing, but I could still hear it. I asked my then partner if he could hear it, and he couldn't, but a few nights later, he could hear it, and I couldn't.
A few nights after that, I went for a bath, and due to the lights not working in the upper part of the house, I had to use a lamp just outside the bathroom door. I remember placing it on the step, and when I came out of the bathroom, it had moved, but no one had been upstairs other than me.
My then partner also saw a shadow on the wall near the stairs, thought it was me, so checked, as it was a figure of a young girl/woman, and when he checked, I was asleep.
Some time after all that, we were sitting in the house and we heard a huge scream, went outside to see what was happening, and the woman who lived down our street was being dragged by something, but we couldn't see what she was being dragged by. Her young son was left in the house, and we could hear plates being smashed and things being thrown. They left the house, and the house was boarded up and not lived in again.
As far as I know now, all those houses have been pulled down and new houses built on that land.