I do think it is quite funny that my Ouija board says that it is a registered trademark of Parker Brothers (it's written on it, it doesn't spell it out for me, ha ha).
Belief is a personal thing. Some find their truth through books, others through personal experience, and others through Ouija boards. If someone believes their Ouija board, it's certainly no stranger than some of the more commonly accepted beliefs out there. And I'll just leave it at that.