A quick, easy to make, and actually pretty powerful speaker system; made from an Altoids tin and a cheap speaker system I bought at Ross. I know tons of these Instructables already exist, but it's my first, so I'm doing something simple.

Step 1: Components

You're going to need:
Altoids tin
Speaker/s(You can buy the little iPod speaker sets for pretty cheap just about anywhere.)
MP3 Player/iPod(for testing)
Needle nose pliers
Wire cutters/Scissors
Metal File(optional)

Step 2: Prepare the Altoids Tin

Using your wire cutters or scissors, cut a hole into the lip of the Altoids tin, and its lid, which is large enough to let the wire of your speakers through. There are ways to build these so that just the headphone jack sticks out, without the wire needing to be pulled out to function correctly, but I don't know how to do that.
You can use your pliers to bend the edges around themselves, making a nice, less sharp edge on your tin. Alternatively, use the metal file to smooth them out.

Next, layer the inside of the tin with duct tape. This step isn't required, but it can keep your speakers from sliding around.

Step 3: Place Speakers/wires

My speakers were a bit too large, so I needed to layer them on top of each other. Take most of your wire(keeping about an inch of wire left out) and place it directly underneath one end of the two placed speakers. I put a piece of duct tape on top of the wires to make them look a bit nicer, and make my headphone jack easier to find. To keep the headphone jack safe during storage, simply tuck it underneath the speakers.

Step 4: Finished Product

When you're done, you should come up with a pretty lightweight, compact, and portable speaker system. Since it's an Altoids tin, you can easily fit it in a purse or pocket.

Thanks for reading, and happy building.