John Kestner

Proverbial Wallets

Financial sixth sense


What would you do if your wallet became harder to open as your spending approached or exceeded your budget? Would you think twice about where your money was going? A product designer at M.I.T. who created a working prototype for such a wallet seems to think so, and he may be on to something.
New York Times

With physical money, we intuitively know how much we have and spend, because it literally goes through our hands. The virtualization of money has magnified the gap between our decisions and the consequences. Do we have a grasp of how money comes and goes?

The Proverbial Wallets restore the benefits of tangibility to virtual money. Tactile feedback reflecting our balances and transactions helps us develop a subconscious financial sense that informs responsible decisions.


The Bumblebee buzzes to give feedback you can feel in your pocket for each bank transaction as it happens. The length of the buzz indicates the relative amount, and a pattern indicates deposits or withdrawals.

Mother Bear

The Mother Bear is protective of the money within it when you need to be thrifty. Its hinge resists opening as you're approaching your monthly budget goal.

This is implemented with a small motor in the hinge that uses back EMF to create resistance, essentially taking the electricity generated by operating the hinge and thriftily powering the motor against that movement.


The Peacock swells and shrinks to reflect the balance in your accounts, which you can feel in your pocket. Your assets will be on display to attract potential mates.


The Proverbial Wallets communicate with a cellphone through Bluetooth, using its data connection to get account activity from your bank in near-realtime, and reflect it haptically using actuators. I designed patterns to reflect the character of each wallet, and these were laser-etched and embroidered onto leather and assembled.

I collaborated with Daniel Leithinger for the original concept, then refined the design and made these models with the help of Emily Tow's soft-goods skills.

Exhibited at Ars Electronica. Press: NPR, CNN, Gizmodo, Boston Globe, Boston Herald, Discovery Channel Canada, Designboom.