In Ann Arbor, Michigan, David Zinn does street art with chalk – on brick, concrete, or whatever else will take – and the images stick with people, long after they’re washed away by the rain. Below are 16 images that will make it easy to see why once you’ve seen some of his work, you aren’t likely to forget it! I wonder if he sees his shadow or just a bunch of smiling faces. Flying pigs and adorable squirrels. Flying pigs love daffodils.