Designers and brothers Aaron and Erik Melander wanted, like me,an ultraslim wallet that would hold credit cards only. Using a piece of two-inch elastic, they came up with the almost excruciatingly simple design you see here.

Doesn't look like much, does it? How do you think it would do up on Kickstarter, do you think this is something that people would want? Well, I can tell you:The brothers Melander had their Supr Slim Wallet successfully Kickstarted earlier this month, with a shocking $203,488 worth of pledges exceeding their $10,000 target by a factor of 20.

Aside from its minimalistic slimness, a secondary benefit of the Supr Slim is its stretchiness. The elastic allows you to carry a lot of cards or a little, stretching to accommodate. It is the perfect application for the material.

I'll stick with my train pass solution for now, because its transparency means I can see which card I'm pulling out. But there are 6,237 Kickstarter backers who don't have this need, and now the Melanders are in business.

This is a great example of identifying a problem and crafting an exquisitely simple, materials-based solution. It's also, recent rendering ban debate aside, a fantastic reminder that accurately guessing what people want on Kickstarter can really launch you into the upper deck.