Apparently, you can build a compass with a glass of water, a needle, and a anything that will allow the needle to float, like a piece of cork. You will also need a magnet. Rub the needle about 30 times one direction with the magnet. Stick the needle through the cork, and place the cork and needle in the glass of water. How wonderful! Instant compass.

I was watching a movie, and this guy rubbed the needle on his shirt (static electricity). He then placed the needle on a leaf which was placed in a small puddle.

So if you're lost in the forest, don't blame me if this doesn't work.