The next time you travel to Japan, you might not have to stock up on yen (or bring your credit card) to go shopping. As of the summer, the country's government is testing a system that will let you use two fingerprints to make purchases at key tourist locations, such as hotels and restaurants. You'd only have to register your fingerprints at the airport to start shopping, and you wouldn't even have to worry about showing your passport when checking into your lodgings, like you do today. Only 300 locations in a handful of areas (Atami, Hakone, Kamakura and Yugawara) will participate at first, but it should keep expanding to the point where it's available nationwide in 2020 -- conveniently, right when Tokyo is hosting the Summer Olympics.