'Zrób komuś dzień dobry' means 'make someone's day' - not in a violent Dirty Harry kinda way, but with a more cheerful approach - what this act involves, we'll leave for you to decide. The mural was created by Dutch artist Loesje, who lives in Warsaw, and follows the artist's usual written mural style. Other than murals, look carefully as you walk around the city and you'll see Loesje spray tags on pavements and pillar boxes!