I know this is a bit of a stretch at first, but if you really think about it, the DS should be able to be a part of the Wii Fit regiment. It will be great because you can implement the DS as part of the motion sensing balance pad. R4 DS would help to save the info on the DS so you can custom tailor your workout to yourself. As you carry your DS around with you, it can serve to remind you of when to eat and what to eat and remind you of how many calories you are taking in.