Nikolas Mavresis developed this great idea of an interactive card game.
Show a deck where actions and nouns are randomly written onto the backs of a Poker Deck. By combining an action from a black face card and a noun from a red face card you can combine thousands of possible activities. When naming any two cards the spectator will select an activity he should have to do. But first, let another spectator select any playing card.
After showing possible different outcomes the named cards are selected. The activity from these both cards are showing the sentence: Open the Box!
After showing other possible predictions in different locations, let the spectator open the card box that was in full view on the table all the time: he will find the chosen card as a prediction.
English video instructions, plus written instructions to prepare your deck of cards (any language is possible) in English and German.