No personal experience here, although I have heard some funky stories on the matter from people, and though I am posting here, please don't take my word for it (even though I personally believe it all to be bullclap)
How does the Ouija board work though, might I ask? Sure, people may think think or believe you get messages from spirits, demons or ghosts. Yeah, okay then. That's possible, but then again, have spirits, ghosts and demons actually ever been proven to exist? Witches were said to exist before, and that people saw tham, although during the Dark Ages when thousands of women were burned to death at a stake, did people find out that witches never had existed in the first place and that normal people were burned out of superstition and ignorant beliefs. Sure, unrelated to the ouiji matter, but it does to show that a common conception can be wrong no matter how many people believe it.
Mostly, to a cetain extent, I believe that those using the board either consciously or unconsciously select what is read. To prove that an ouiji board works and that spirits do indeed channel through them, it would be simple to try it blindfolded for some time, having an innocent bystander take notes on what letters are selected. Usually, the result will often be unintelligible nonsense of randomly selected letters. Okay, so what makes the pointer move then, even when people don't intend to choose what is chosen? People's suggestions, myths, beliefs and stories. Such influences direct the mind and affect motor behavior. What is purely physiological, however, can appear to some to be paranormal. In other words, if you believe this stuff and are trying to get the spirits to answer questions proving that they are all-knowing, and you ask a question that you already know the answer to (for example, "What's my father's name?"), odds are that your own hands will do the rest by spelling out your answer. That's where trying it blindfolded comes in (provided you haven't memorized the board, obviously). If it's really spirits, they should be able to guide your hands no matter whether you can see or not. But if it's you doing it unconsciously, then obviously the blindfold would screw things up.
Since this test hasn't really be officially taken, I can't really speak for it as a whole. As for an actual spirit causing the movement, I'd say fake, but who knows if the energy of another mind is helping each participant to move. Either way there are better games to play at a party, and none likely to unleash a malestrom within your vicinity. Try Twister instead,
mm'kay?