Apples are probably one of the easiest materials to use in making a simple, makeshift pipe.
You will need:
An apple
A pen or pencil
A pipe screen (or you can poke holes in aluminum foil, which could be hazardous to your health, consider yourself warned)
1. Remove the apple's stem.
2. Push the pencil down the hole where the stem was into the apple, stopping about halfway to the bottom of the apple.
3. Poke the pencil through the side of the apple, being careful to pass through the hole made in step 2 and out the other end of the apple. Only the tip of the pencil need poke through the other end of the apple.
4. Make sure that all of the holes drilled through the apple line up by covering one hole and blowing into another, air should escape out the remaining hole.
5. Gently poke the screen into the top hole of the apple, bending it slightly to form a bowl. This is where you will be placing the smoking material. One of the holes on the front will be the mouthpiece, the one opposing it is the carb.
When you're done remove the screen and eat the apple, it should have an interesting "smoky" flavor