It wasn't until Nintendo had two screens to play with that they figured out we wouldn't mind oversized portable gaming. Had they realized it earlier, they might have come up with modder John "Baccteria" Grayson's BigBoy Advance.
That's right, the man who brought us the 18-console Project Unity has crafted a very large Game Boy Advance, and crafted it quite ingeniously. Instead of taking apart a Game Boy and spreading the bits out, he used a third-party Super Nintendo board to power a third party Game Boy Advance adapter.
The result is massive fun in the palm of two hands.