Over the next three months a cluster of East London ATMs will be offering customers the chance to withdraw cash using written prompts in Cockney rhyming slang, the area's colorful and often impenetrable dialect.
ATMs run by a company called Bank Machine offer a language option allowing customers to enter their "Huckleberry Finn" instead of their PIN, and rather worryingly informs them that the machine is reading their "bladder of lard" at a prompt about examining their card.
The origins of Cockney rhyming slang are obscure. It is thought to have been used by market traders who needed a way of communicating without tipping off their customers.
It works by replacing a word with a short rhyming phrase. For example: "Money" becomes "bread and honey," which in turn is shortened to "bread." Similarly, "head" becomes "loaf of bread," and then just simply "loaf."
Few use the slang with any regularity now although most Britons know a few common phrases, such as "trouble and strife" for wife and "apples and pears" for stairs.
Gabriella Alexander, who made a withdrawal from an ATM, near Spitalfields Market, said the stunt was fun. But she added that that withdrawing "sausage and mash" - or cash - "made me a little uneasy."
Slaney Wright, a 32-year-old charity worker, attempted to withdraw money from the ATM but visibly tensed up when she realized the machine was talking to her in Cockney slang. She immediately canceled the transaction and ripped the card out of the machine.
"It looks like someone's been messing with it," she said.