The Natsu Wallet by Kisetsu Collections — which started out as a successful Kickstarter campaign — proves you can carry a minimalist wallet without sacrificing style or functionality. Made from a single piece of PU saffiano leather with oiled edges to prevent fraying, the Natsu can hold 4–6 cards comfortably, or 8 cards snugly.

There are two other features that set it apart from many minimalist wallets:

1. RFID protection — This helps ensure the safety of personal information stored on a chip, if your credit card has one.
2. "Anti-coin-spill compartment" — A place to store any coins you may accumulate throughout the day. It's a pretty tight fit, so I wouldn't expect to retreive coins from it often; it's more of a "dump it out at the end of the day" sort of thing. You could also use this slot to hold a key, if change isn't a problem for you.

As you can see above, the Natsu comes in a variety of colors, with prices ranging from about $19 to $25. As of this writing (Oct 4th, 2015) you can use the coupon code WALLETDIET to get 10% off.