What happens to those who rely on spare change, when there's no more spare change?
London's homelessness problem is impossible to ignore, though we do try our best. 8,000 people slept rough last year, a number that's doubled in the last five years and tripled in the last ten.
And more often than not, the response to panhandlers of 'no, sorry' is true - fewer of us are carrying cash, relying on contactless payments for small purchases. But what if someone who is homeless could accept contactless? Would we be happy to tap to help pay for a bed for the night?
An Amsterdam company, N=5, has created a jacket equipped to accept contactless payments. The money can then be used to pay for a bed in a shelter.
It's an admirable idea, and the rise of contactless and decline of cash is going to create issues like this that will need to be addressed - such as those who do not have a bank account, charities that rely on donation tins, and jobs that rely on cash tips.
It's not clear if this is the best solution, however - while the contactless readers will only take a Euro, how willing will people be to risk tapping their card on a reader that's not in a store or seems 100% official? And there is a whiff of puritanism about how the money can be spent on just the necessities and self-improvement.
The term 'cashless society' is often used to talk about the shift from cash to card payments, but what happens when it creates a divide - a cashless society and those outside?