Parc André Citroën, Paris
I love this simple idea made with cinder blocks. You could do a moss paint on them so they get covered in moss. Pretty.
Put in blender: one can of beer, a few handfuls of moss, one teaspoon of sugar. Paint on well and mist daily until it grows.
Love these moss walls and rainwater collectors by Wayward plants
Gallery of Living Walls - Habitat Horticulture This would be pretty cool to do if I had all the time in the world!