Back when the Famicom became popular in Japan, Nintendo released alot of add-ons for their console. One such add-on they made was a modem + a save-data card for home banking. Nintendo also released a rare console named the Data Ship 1200, which was a banking system and Famicom built in 1 system. These Data Ship 1200 consoles use data cards for the banking instead of cartridges.

These banking modems included a special controller with buttons custom for home banking. These units are over powered with ports, switches, and other useful features.

I am not sure why people would use a Famicom system to do home banking. It is totally beyond me. I guess this is another one of these weird Nintendo inventions not well known, and not well used. Anyone ever use one of these for banking? It would be interesting to know what Nintendo was thinking when they released this. It never made it over to the US either, probably because US gamers wouldn't use consoles to do their banking.