Zelda Four Swords Adventure is a great game, but finding the 4 GBAs, a GameCube, GC-GBA linkcables (and Zelda Four Swords Adventure itself) is difficult. It is in theory possible to run Zelda Four Swords Adventure in Wii-mode and tunnelling all the link-cable data through wifi to DS.
To do this:
ZFSA must run on Wii hardware natively to access the wifi hardware. This is the most difficult part. After this, maybe a custom (game-specific) IOS to tunnel the linkcable data through wifi, or a patch to disk image itself.
A flashcard in DS-mode can run a *very* barebones gba emulator at full speed on DS. Ideally, a Wii/DS connects via Wireless Multiboot (DS Download Play). The emulator runs in DS-mode to access the wifi hardware (no link-cable port in DS). It emulates *only* what is needed (parts of the GBA bios). I would think the 4mb of RAM in a DS is enough.
There is always a possibility of using the extra hardware in a DSi (or that media-player flashcard with a cpu), but that is a last resort IMO
Officially?: Nintendo have ported many games to Wii (Pikmin, Metroid Prime etc) and can use Wireless Multi-boot (DS Download Play) on any DS (as they know the private key). An unedited trimmed binary is 126mb, so a 128mb Virtual Console (WiiWare?) game is conceivable.
Thoughts?