I built this MP3 player from a 4GB COBY MP3 player, and a used NES controller. All of the buttons work except for Start and Select. It runs off of 1 AAA battery. And connects to computer through mini USB. To access battery and usb connection you have to remove 4 screws.
You get one NES controller MP3 Player, one AAA battery, and one right angle mini USB cable (when you open it up you'll see why you need a right angle cable).
I want to sell this so I can build another one

So how much would you pay for the coolest MP3 player in the world??? Think about all the friends you can impress with this one of a kind novelty item...
OK, I'm no Billy Mays, but this thing is pretty sweet, so go ahead make me an offer.

