It'd bulky and horrible to see, but yes, that could work. I'm still missing the point though since having a processor and some memory pretty much makes it a flashcard... which do already exist
Wait; flash carts already have processors and additional memory which they can use to do stuff like this? I
do own one (an Acekard 2.1, to be precise,) and I'm pretty sure that it uses my DS's
internal processor and memory to do its work. What I want is something that can take a ROM
hack from an
existing flash cart and, at least temporarily, apply it to the game read in from the cartridge without creating a ROM. If the respective save file couldn't exist simultaneously with the one for the normal game, then it could be exported to the flash cart. People could still use flash carts, but I just want to be able to play a
derivative work, specifically the 'HGSS - Kris as Female Protagonist' hack, over my existing
Pokémon SoulSilver Version cartridge without risking the legal hassles of downloading its ROM; I already have too many of those and am considering buying their actual cartridges. Maybe this could be averted by a device that first loads a program which can prevent cartridge assets from loading and replace them with hack assets from the flash cart before loading the cartridge. That, though, might require somebody to program something like Microsoft's Windows ReadyBoost into AKAIO, the Acekard firmware, in order to prevent the program stack from running out of memory.