I heard of these things recently, I have not used Siri that much, so these have probably been known for a while.
You can ask siri to "Flick a coin" for you, if you do ever need to settle an argument and don't have a coin, as long as one of you have an iDevice with you, then the decision can be made.
The other way is you can get Siri to "Roll the Dice" so if you do have a board game and you open it up and one of the dice is missing, no fear Siri can roll the dice for you to let the game and the arguments commence.
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