| Bung Enterprises ltd. is a Hong Kong company that produced devices for game consoles, most notably development/back-up units like the GB Exchanger for the Game Boy and the Game Doctor/Professor SF series for the Super Nintendo/Super Famicom.
You can load these devices with ROM data and connect them to your console, where they will simulate a game cartridge. This made them cheap alternatives to Nintendo's official development kits. Of course, they could also be used as tools for piracy.
Eventually, Bung were sued by Nintendo and had to shut down their operations, so their devices are no longer available.
Their website is still online at the time of writing, at
http://www.bung.com.hk. | 
