Web Based Photographic Graffiti

[shoelaceman]

Hi all, I am a photographer/artist researching a new project. I am starting a group that places web url's in locations where they are taking a photo. That url will then take the viewer(someone with a web capable cellphone) to the image the user took earlier at that same location. I hope to confront the viewer with the idea of time and place. While thinking about the project the connection to graffiti popped in my head. My main problem has been what does a user get from participating in this activity and how to convince them to do it? What motivates you to make your work? Does this idea interest you? Any thoughts would be great, thanks.