I am not sure if this counts as interactive media, but it is something that I find extremely interesting. A few years ago there were a Kurt Wenner began to do chalk drawings in cities that he went to. He created large three dimensional chalk drawings that are extremely realistic. After he started other people began to do this as well, I think that it is an extremely interesting and amazing that he can make it look three dimensional. The reason I put it up in a blog about Interactive Media is that people interact with the drawings, (ex: if there is a hole in the sidewalk they walk around it).

Kurt Wenner's Website
http://www.kurtwenner.com/pavement_gallery_4.html