It is a simple idea with simple products.
Thousands of tonnes of potatoes are sold directly from the farmer to the consumer, cutting out the costly middleman and so slashing prices by more than half.
The seed of the potato movement was planted in northern Greece a few weeks ago and is proving so successful that it's now come down to Athens, growing ever more popular as Greeks struggle with the worst recession in modern history.
"Salaries are very low, taxes are very high and the price of products doesn't seem to follow," says Sofia Manidou, one of those waiting in line.
"We have to pay a lot of money for basic products like potatoes. This is the potato revolution and we hope to see revolutions of other types of food too because we are in great need of this."
And that now seems likely, with similar schemes in the pipeline for rice, flour and olive oil. It's a movement that benefits both sides, with farmers earning for what they produce, without paying large intermediary fees to wholesalers.
Some supermarkets have been forced to reduce their prices in response.
Stelios Ioannidis is one of the farmers taking part, off-loading dozens of sacks of potatoes to the eager customers.
"The middleman exploits us by buying our products at low prices," he tells me. "We want to help the consumer in these difficult times. This sends a message that a few people can't profit at the expense of all of us."
'A little humiliating'
It is that solidarity, that determination to fight back which is, in a sense, a positive by-product of this crisis.
Greeks are finding new ways, new ideas, to deal with the deepening recession, refusing to accept the status quo.
The potato sales are now organised by municipalities keen to participate.
Customers pre-order the quantity of potatoes they want. After paying, they're given a receipt, which they then present to the farmers, who hand them the right number of sacks.
From afar, the whole scene is strangely reminiscent of food lines - and this in a European Union country. "It is a little humiliating," admits Lefteris Roubelakis as he waits patiently in the queue.
But as austerity bites ever deeper, the movement is meeting the needs of a squeezed nation.
Unemployment here has now soared to 21% - 51% among the youth - and 15,000 more public sector jobs are to go this year. The minimum wage is to be slashed from 750 euros (£624) per month to just 500 euros.
"The situation is very bad," says Manos Psarakis, another customer. "We have to feed our families and every day that becomes more difficult."
He pays 19.50 euros for 60kg (132lb) of potatoes, which he shares with his parents. It's less than half of what he would pay in the supermarket.
"Twenty euros is definitely worth saving," he says. "Today we count every cent."
Many of those queuing up are Greece's middle-class, particularly badly hit by the cuts.
Brain drain
Among them is Kostas Hadzigianellis, a civil engineer working on state construction projects, which have almost totally dried up.
He invites me home where he and his wife, Katerina, a teacher, tell a now familiar tale. With two young children and salaries that have dropped by almost half, they are struggling.
"We have had to cut things from our lives and from the lives of our children," he says. "We are just trying to live, but it's very hard."
I ask of his plans for the future. "We have no future here," he says. "I believe I have to leave Greece, to find another country that can offer a better life first for my kids and then for my wife and myself."
Ordinary Greeks queuing to save a few euros for basic goods and an ever-growing brain drain of the middle class: these are the signs of a society suffering in a way few could have predicted.
And civic initiatives are springing up in response, the potato movement among them. It is an act of defiance that is taking root in a changing and deeply troubled Greece.
.bbc.co.uk
