The SNES is old enough that any hankering to play Super Mario World can be satisfied entirely by emulator. Still, here's a USB hack that lets you plug old carts to a PC.
Hackaday reader Matthias rigged up this solution, which makes the cart show up on a PC as an external drive with the ROM file inside. From there, it's playable on one's choice of emulator.
Admittedly, the number of cases in which one has a working cart but no working console, and a working emulator but no working ROM, are probably quite low. But I remember Dad asking me what was the point - when free WiFi is so plentiful - of jailbreaking my iPhone and rigging it to serve as a dialup modem for my laptop. "Self esteem," I said.
In other words, whatever this thing does for you isn't important; the thing you made it do, however, is. Good work, Matthias.
USB Reader for SNES Game Carts [hackaday]