The three FinTech startups worth watching this week take markedly different approaches to creating products: two fill needs in underserved markets and one adds a new take on a luxury product to an already well-served market.

• BLK – Incubated by Curious Minds, BLK takes the “black card” experience of American Express’s Centurion Card (not to mention Magnises and others), such as a personal concierge, automatic upgrades at hotels and auto rental outlets, and more, and extends it to just about anyone who can afford it, meaning high-net-worth individuals. The exact mechanics of the service are unclear, but it seems to be mobile-based and ties into members’ financial accounts. Calling all millionaires!
• Currency Mood – Currency Mood describes its service as “Waze for bureau de change,” or private money changers. The service lets consumers see the bureaux de change in their area and compare rates to find the best deal available. The company fills a need for a large region: those living on the U.S.-Mexican border. This area essentially has dual currencies, the peso and the dollar, and by helping consumers get the best exchange rates in this environment, Currency Mood will save its customers money and, perhaps, give a boost to the local economy.
• PotCoin – Marijuana sellers the U.S. have a problem: Peddling pot may be legal in certain states, but the federal government does not (yet?) agree. Consequently, banks are unwilling to allow marijuana merchants to accept credit cards in their stores or even open deposit accounts for their profits. Therefore, THC traders use cash by necessity, leaving them ripe for robbery. And it’s not just crooks they need to watch out for — federal agents have seized cash along with the cannabis when sellers leave the protected zones of their stores. PotCoin is a cryptocurrency designed to solve this problem. The blockchain system insures that there is a record of each transaction, and the elimination of large amounts of cash lessens the danger to the seller. The PotCoin team seems to have a solid system in place, but the challenge will be to get the currency in wide enough circulation for the price will stabilize.