Multiple Use Tools

Bandana 
This is a great list of things you can do with a Bandana.    They probably covered most of the possible uses but I bet you can find a few more.

Duct Tape
I've used it to hold down a bandage, sealed a leaky garden hose, and patched my shoes.  This link gives you many good ideas.

Bow and Arrow 
The use of this tool is great for your mind, great for your body or at least your upper body, and also acts as a silent means of taking game.

Smart Phone
These things are getting good, very good.  I'm waiting for the Phaser App.

Leatherman
This is what we always thought of when thinking of a multi-use-tool.  The biggest downside is the pliers that any of these have.  Be careful not to pinch your hand or you will learn to yodel like a Swiss Mountain Climber.


Other options.

CRKT - multi -tool