The widespread adoption of credit and debit cards means, for many people, the cashless society is already a reality. However, this means the simple system of checking how much cash you’ve got in your wallet before making a purchase is no longer an accurate reflection of your finances, making it all too easy to succumb to temptation and overextend yourself financially. The Proverbial Wallet project at MIT is looking at “un-abstracting virtual assets” with wallets that provide tactile feedback that reflects a person’s current financial state.

The wallets devised by the folk at MIT’s media lab all use Bluetooth to connect to a mobile phone and make use of its data connection to get financial information from the user’s bank accounts. There are three different wallets that use three different forms of haptic feedback to help with our modern pecuniary predicament.


The Bumblebee is a wallet that uses a vibrating motor to ‘buzz’ whenever the bank processes a transaction on the user’s account. This is designed to encourage a conscious connection between the act of handing over your credit card and the removal of your hard-earned cash from your bank account. The length of the buzz reflects the size of the transaction and the pattern indicates whether it is a deposit or withdrawal. An added benefit is that it also alerts the user to fraud when they get a buzz without making a purchase.

Mother Bear

The Mother Bear is a wallet designed to promote saving. It features a hinge that keeps the wallet shut tight when the user goes over budget. The trigger point for the hinge can be mapped to a monthly budget goal and the wallet will become increasingly difficult to open as the budget threshold is approached. In other words, the tighter the finances, the tighter the wallet.


Finally there’s the Peacock. So named because the wallet grows and shrinks relative to the user’s bank balance, thus providing a way to show off your financial worth to potential mates. If you’re account is a little light on then the servo in the wallet will keep an embedded arm parallel to the wallet surface, but as the balance grows the arm will move towards being perpendicular, resulting in a wallet of George Costanza-esque proportions that is sure to set many a fair maiden's heart aflutter.

At the moment each of the three wallets use only one form of haptic feedback, but the developers say that in the future, all three types could be integrated into a package the size of a credit card, which could be inserted into any wallet. Instead of the bulky servos and motors currently used, such an all-purpose package could use shape-memory metal that bends to create the illusion of a bigger wallet, or changes the stiffness of the wallet hinge.

The Proverbial Wallets are currently at the working prototype stage and are tough enough to sit on. But if they’re going to restrict access to a person’s credit cards, they’re probably going to need to withstand a lot more punishment than that.

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