Week a sustainable city should encourage people not wasting resources and recycle more. Some projects like this basketball court sticker placed around garbage cans to make throwing out litter a game can encourage people to recycle in every day life
"Vertical Landscape" by Eiko Ojala. It looks like a paper landscape but the artist actually works digitally and hand-draws all the elements to look like they're cut out of people. (Hint: the shadows help!