Coin: Coin is an electronic credit card that replaces multiple credit cards by storing credit card information. You click through multiple credit card profiles, pick the one you want to use on the E Ink-like display, and it’s just as if you’re using that credit card. This is a great idea for those who carry lots of credit cards and debit cards. But it doesn’t solve the real problem: You carry too many credit cards. The solution: Get rid of all your credit cards, except for one. And carry that.