I'm not advising that people go out and buy a Ouija board, but I do want to share my experience which is from the opposite spectrum of what has been posted so far.
I bought a Ouija board after reading one of the Seth books by Jane Roberts. If you aren't familiar with her, she is a very well-respected channeler from the 60s. The entity she channeled, Seth, was wise, funny and brilliant. I wanted to channel and receive such wonderful guidance for my own life. Jane first got in touch with Seth via the Ouija board, so I figured that would be the best way for me to start.
From the start, I always set my intention that I only wanted to reach a spiritual guide of the light for my highest good. At first the board just moved in jibberish. After a few tries, it began to spell out words. The spirits I first spoke to just seemed to be dead people, not spiritually advanced and not connected to me. For some reason, I kept trying and one day I got a spirit who said she was from my boyfriend's soul group. She loved him very much and had very good advice on a work situation he was having difficulty with.
She introduced me to another spirit who said he was from my soul group. He had wonderful advice and insight into my life. He told me that I had to learn to meditate and build up my energetic "muscles", that using the Ouija board was like me picking up a 100 pound weight with my skinny arms.
At that time I was pretty impatient to practice meditation. I refused and they told me that we wouldn't be able to communicate anymore unless I started meditating. After that when I tried to use the board, nothing would happen. I felt so sad to lose the connection so I finally started meditating. After meditating regularly for awhile, one day I just started channeling.
I guess the conclusion to my long story is that the Ouija board is a tool to open the psychic channel. We are all energy and whatever we vibrate to we will attract. Because most of us are not aware of what we're carrying around energetically, especially fear, it's best not to use the Ouija board. We can develop the ability to connect psychically the safe and natural way - through meditation and spiritual development.