What is your weapon of choice? Can be anything to a simple stick to an RPG. Can be ranged or melee, but keep in mind you only have the one and once it's gone its hand-to-hand combat for you, a new weapon is not an option in this scenario so make it count. Keep in mind if you choose a ranged weapon you can re-supply but depending on your choice, it might be difficult to locate. Also give your current location as that can factor in to what is available around you.
For me I choose the simple steel crowbar. Light weight and versatile. I am currently residing in the east coast of Canada, but really a crowbar can be found just about anywhere.