Well, there's the YES/NO card, and the "Ouija" board card with the planchette.
Have you ever played with Ouija or similar fortune-telling boards? A mentalist could manipulate one (combined with some secret background knowledge obtained either on the fly or in advance) to make an impressive performance.
The YES/NO card is not much different from flipping a coin, except that with some sleight of hand the right magician could rig the results.