Last weekend was the weekend of the 'altra economia' in 'la città dell' altra economia' in Testaccio.
In La città dell' altra economia there is a bio-shop for food, one for other items including fair trade products, a Bio Bar and a Bio restaurant. But last weekend there were all stands with bio food, clothing, books,etc. as well. Even the bio-guy from Biolà* was there.
I ate the best pannocchia ever from one of the stands. The shops are ofcourse always there and one Sunday per month the stands will return.
If you are in Rome definately worth checking out.
*Biolà is a biofarm in Fiumicino, but every week they travel to different places in Rome and set up there with their little van to sell milk straight from the cow, meat, mozzarella, ricotta, honey,... You can find the schedule, products and prices on the site.