Volos is also one of several Greek towns with a more formal type of barter network, which uses a currency called Local Alternative Unit, or TEM in Greek. One TEM is equal in value to one euro.
People sign up for free on the barter network's website, where they can post ads on what they can offer or what they want. Members exchange goods and services — for example, English and computer lessons, baby-sitting and plumbing repairs, medical visits and car-pooling — amassing TEM credit into an online account.
Some shops also accept TEMs, in the form of vouchers that function like checks.
Optician Klita Dimitriadis explains how it works. On a pair of 100-euro glasses, she'll take 30 percent in the alternative currency. She needs the 70 euros, she explains, in order to pay her employees, taxes and rent.
Dimitriadis then spends her TEMs at a monthly open-air farmers market, or in exchange for other services.
Over the past year, TEM members in Volos have grown from a few dozen to more than 500, and the movement has attracted Athens' attention. In September, parliament passed a law giving barter networks nonprofit status.