"Why the hell didn't I think of this first?" is what you would file this one under if you were the type of person who went to great lengths to file anything and everything. Also, you ought to seek professional help.
Basically, this is what happens when you cram the innards of a Game Boy Advance SP into an original Game Boy ... and do so in such a way that it all looks highly attractive. Why yes, it even has rechargeable batteries and can play GBA games that require the L and R buttons.
If Nintendo were to make slightly smaller Game Boys -- my pockets, they are kind of tiny -- with the same level of style and functionality showcased here, I'd be all over that.