This may be one of the more expensive ways, from a hardware standpoint, to get a SNES emulator up and running but if you have an iPad and an iPhone (both jailbroken, of course) then SNES (HD) may be worth checking out.
The basic idea is that you load your SNES roms into a specific folder on your jailbroken iPad and then connect your jailbroken iPhone via Bluetooth using a second app that turns it into a touchscreen SNES controller. Pick your game from the list and then hit the virtual SNES console’s power button to set everything in motion.
Here’s a demo video:
Looks pretty slick. The price is right, too.
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