You will need a cheap box with a handle (I got one from Marshall's, $6), an iPod (any sort), and some speakers that DON'T need external power (Radioshack, $10). This way you don't have to plug your box in and its completely portable. You will also need a compass, ruler, pencil, and some foam.
use the ruler to measure the box. place the ipod in the center and the speaker holes on the sides. notice that my speakers are square but the holes are round. it doesnt matter, but the finished product looks better. we cover the holes later so you cant even see the speakers.
Step 3: Foam
now cut the foam to fit inside your box. This step gets REALLY messy so be prepared to clean up or do it outside. Even after the initial cut you will probably have to make some adjustments. For the speaker holes, you can just cut right through, but for the ipod hole, it cant be too deep, or hollow. you dont want the ipod to fall through. Just scrape it out so its deep enough to hold the ipod.
Step 4: Assembly
now that everything fits, just put it together. put the speakers in the foam, and then the foam into the box. be sure to leave the headphone jack exposed so it can connect to the ipod.
Step 5: Finishing Touches
Now that its all together and workin, all you have to do is get some nice fabric to cover the speaker holes. put it inside the box and close the lid to have a perfect iPod Boombox!