I finished a new project, so here it is. The whole thing cost less than $35 including the soldering iron and solder. It's a 1GB mp3 player. It isn't quite finished in the video but it is definately fully functional. There are a few tweaks I need to do to polish it off a bit.
I had planned on doing this for a LONG time and there was virtually no one on the net with REAL info about how to make one. All I really needed to know was what MP3 player would work best (and be cheap) to hack into bits and remap the buttons. Every MP3 player I got my hands on to frankentien wouldn't work because of the shape and size of the curcuit board and how the buttons worked. This dude had found one that seemed to work but I didn't like how he went about hacking it apart so I modified it quite a bit to make the work much more simple, cheaper, and in my opinion more durable. Props to him for finding an MP3 player that would work well and helping me finish an idea that I'm sure SO many geeks have had.
For sure this is version 1.0 and 2.0 will come around when I get time and motivation to do it. I have some mods that I would do to this to make it better and I also have ideas to use completely different guts inside it but it would cost more and be much more difficult to solder.
Check out Instructables.com and search for NES MP3 and you'll find the one I used for reference. I will eventually post all the pictures I took and probably make an intructable, just so you can see what changes I made. In mine there is a LOT less soldering (I hate soldering)