Amazing! “Water Light Graffiti” by Antonin Fourneau… check the video…
“The “Water Light Graffiti” is a surface made of thousands of LED illuminated by the contact of water. You can use a paintbrush, a water atomizer, your fingers or anything damp to sketch a brightness message or just to draw. Water Light Graffiti is a wall for ephemeral messages in the urban space without deterioration. A wall to communicate and share magically in the city.”
More information on: digitalarti.com/wlg