THE EFFECT: A coin is clearly placed into the magicians hand. The magician rubs the back of his fist and the coin vanishes! A great quick seemingly impromptu coin vanish.
THE SECRET: You need to place a strong magnet in your pants pocket. The coin needs to be magnetic so it will stick on your pocket when you bring the coin up to it.
Show the spectators the coin then place the coin into your fist and turn it palm down. Gently rub the back of your fist in a magical gesture, use this as misdirection and allow your fist to secretly open slightly so the coin sticks on your pocket.
Move your hand forward so your arm is covering the coin on your pants. Now open both hands to show that the coin has completely vanished. Make sure to show the back of your hands too. The coin will be nowhere to be seen!