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@Jake From Wikipedia:Nintendo DS games use a proprietary solid state ROM "game card" format resembling the memory cards used in other portable electronic devices such as digital cameras. It currently supports cards up to 2 gigabit (2048 Mb or 256 MB) in size (with ASH: Archaic Sealed Heat being the first DS game to use a 2 gigabit card),[23][24] which is four times the amount of memory that the largest Nintendo 64 cartridge was able to store (512 Mb or 64 MB). The cards always have a small amount of flash memory or an EEPROM to save user data such as game progress or high scores. The game cards are 33.0 mm × 35.0 mm × 3.8 mm (approximately half the width and half as thick as Game Boy Advance cartridges) and weigh around 3.5 g (1/8 ounce).
I think Dragon Quest IX will use 2 256MB cartridges.
