I never believed they were real until I used one, then weird stuff started happening to me and my roommate. I didn't believe in the supernatural for a while, but so many weird things happened (felt something laying on top of me at night, seeing flashes of blue light, hearing creepy songs come through my speakers when the computer was on sleep mode and pandora was off) that I am now almost inclined to believe it's all real
But that's just me, I still like to believe there's no such thing as ghosts, but if that stuff was all in my head, I must have some kind of superpower, cause I saw and heard stuff all the time after using that ouija.