Some dupes
Dupe a backpack or items:
1. Put items into a backpack (optional)
2. Put backpack or items into a tent/vehicle/other player's inventory
3. Alt + f4
Your inventory gets rolled back to before you put them in, and they stay in the other inventory.
If you are doing this with another person, you can also just drop the backpack instead of putting it onto a tent/car.
Base building Script materials dupe:
1. start smelting a material ( anything over a 5 second smelt time works)
2. get into a car
3. open up your inventory and put the items into the car
Your items will be put in the car, and won't be used up. You still get the finished product.
tested it out but it seems it dosnt work for Original Dayz...D: