LE CONCEPT. A concert hall connects members in a restricted geographical area. Each offers a service, but there is no charge for it. Nor do we exchange “a helping hand for a helping hand” but “a helping hand for time”. These “time vouchers” are paid into a common pot. “So, we don’t feel indebted,” smiles Joël Grosjean, the president of the association. The services offered are studied on a case-by-case basis, because they must not constitute hidden work or replace the work of a…