Spontaneous Society is a recurring interactive walk lead by Jon Cotner, involving five participants and a “catalog of one-line utterances” that replace “urban anonymity with affection.” You can listen to an audio improvisation of one such walk and see photographs of another here.
“Spontaneous Society provides a communication primer: a lesson in affectionate discourse bridging races, ages, classes; a reminder that the present, barring violence, is to be celebrated before it vanishes into nothingness.”