hyperallergic:

Two Chelsea galleries are simultaneously hosting the same audience-activated Yoko Ono pieces, with collaborative mending of shattered ceramic, sketching of an infinite line, and contemplating river rocks. Yoko Ono: The Riverbed opened last Friday at Galerie Lelong and Andrea Rosen Gallery, and until the end of January the spaces will be gradually transformed by visitor actions.

Yoko Ono Asks Gallery Visitors to Repair the Impossibly Broken