The lights are on
You will need: A dispenser, another player, and a stackable item.
Glitch background: This was a glitch in Minecraft beta 1.6 but Mojang patched it. It seems that 4J studios hasn't fixed it the second time around.
Step one: Set dispenser on the ground.
Step two: Place one stackable item in it. (Do not exit the dispenser screen)
Step three: Have the other player break the dispenser.
Step four: There will now be 64 of whatever item you placed in the dispenser. Remove the stack and place it in your inventory.
Step five: Spread the stack around your inventory.
Step six: Enjoy diamonds or whatever else you duplicated!
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