Throughout the year almost every town has a day set aside for these. Also called 'vide greniers' (literally, empty your attic) these events give local people the chance to sell-off previously loved possessions, family heirlooms, things they have forgotten to throw away plus quite frankly, as is our experience, anything they can turn into a few centimes.
They are often joined by professionals adding a great mix of products for even the keenest bargain hunters. .
You can find out where to find a local brocante here