Tin Can

It's very uncommon for the civilian to think much of daily household items as tools for extreme survivalist situations. The tin can makes for the perfect example.

You could lob the tin can like a grenade...
Use the tin can to reflect the sun, thus temporarily blinding your enemies...
With a quick fold, split and tear down the center wield dual tin can blades...

Besides combat the tin can has an even larger array of applications.

You could reflect the sun down the center of the tin can helping slow boil and purify collected rain water or moisture...

Wear the tin can as a high visibility hat in densely populated urban environments protecting you from lawsuit amidst a possible traffic collision...

Use a piece of wood in conjunction with the tin can for use as a flintstone styled transportation system reducing travel fatigue on long journeys into the great unknown...

A tin can telescope is always a must when venturing out onto the sea. It's effectiveness goes beyond that of merely cosmetic should you happen to have mastered the crafting secret of parabolic glass lenses.

And last but not least, the classic 2 way tin can audio transmitter receiver with a long piece of string.

Make sure to be careful of the can opener. You'll get the hang of it. The best perk of working at your uncles fish n chip shop is it doesn't matter how many cans you drop! As long as you eat them off the floor you are forgiven and will remain amidst his generous employment.