This drawing of 'Golden Eye' by Daria Dzyuba is amazing! He has just used 4 colours (dark yellow, light brown, dark brown and black) and HB mechanical pencil. For the brightness of the eye he has used a rubber and white gouache.
Nagai Hideyuki uses two sketchbooks to create illusions. I was thinking this may be possible to do on the street/buildings with chalk, but in order to view it correctly everyone would have to be the same height, so that probably wouldn't work.