No, I haven't seen a ghost. Although I've been visited by their spirit. The night of my best friends little brother's funeral, I was lying in my bed and there was like a happy face on my wall. Not like :) type happy face. But a face he made quite often. I couldn't sleep because every time I shut my eyes, I would see him lying in the coffin. That wasn't the same person I remembered.
I finally couldn't take it any more and walked to my mother's room. When I shut the door I noticed something on the wall. The light from the air vent was reflecting on the ceiling, it read, "I luv u" just like that. I stared at it for about twenty minutes and then my mother said, "Rachel what are you doing?" I said, "Nothing," and then went to her bed.
The next night and the night after that I checked to see if I was just hallucinating, or seeing things but it wasn't there again. I don't know if it was him, but it was ironic that that happened on the same night of his funeral and not any other night. Also I didn't get to say good bye to him in person, I think that was his way of saying bye.
Another thing, is the night he died, I was awake, and at 12 AM my whole body felt a shiver run down my body. I then got a call the next day from my best friend telling me he died at midnight.
And in my bedroom, I will walk in and my alarm clock radio will be on, when I knew it wasn't on. Or my TV would switch on. And at my best friends house, he switches on fans and light and plays with his old toys.
So I haven't physically seen his "ghost" but I do believe I was visited by him as well as his family. And I was really close to him. He was like a brother to me. :)