This sort of idea could work in the Champ des Possibles.
Je ne peux pas trouvé du texte en français sur ce project. Je ne sais pas pourquoi. Une bonne idée quand même.

The urban authorities asked Melissa Mongiat, Mouna Andraos and Amélie Bilodeau to give shape to an installation that should inspire people to give their vision on a new public space in the city’s newly built Quartier des Spectacles. The artists came up with a spectacular one-day urban intervention that invited passers-by to share what they would like to see, do, or who they would like to meet in this space, and together explore all possibilities.
Here is a blurb about the artists, and their work:
We believe in participation – empowering people to have a place in the stories that are told around them. We research new ways to interact and tell stories. Anything is possible.
We come from the fields of interaction design and narrative environments. With those skills, we design large scale projects that impact cities down to tiny ones that fit inside a pocket. Our projects bring magic to everyday places, behaviors and objects, inviting the public to become active contributors in the process and surrounding environments.
These experiences take many shapes: urban interventions, exhibitions, products, spatial design, events, software applications. In the past, we have created projects for PS1/MoMA and Eyebeam Technology Center in New York, London’s Southbank Centre, Kensington Palace, Arup Foresight, British Design Council, Capitol Film and CBC.
For more information, see their website.
via: The Pop-up City