Homebrew Multiboot loader.
I don't have much experience with coding for the NDS, and i dont know if it is possible, but it could be a nice idea.
Like most of u know the NDS has a RSA singature check when loading a multiboot game, and some people don't want to flash thier DS to remove it.
So it can be a nice idea to make a Homebrew Loader witch loads a multiboot game without checking for a RSA code, and if possible even run from the DS memory and remove itself when the game is loaded, then the flashcard can be removed to start thesame process on another NDS.
Edit: maybe another option is:
If the RSA checker isnt in the write protected part of the firmware, maybe remove it.