Pioneers of the electronic side of graffiti, these guys from Eyebeam are really pushing the boundaries of what can be done on the streets in our age of technology.
This was what their website had to say on their concept.
"The Graffiti Research Lab is dedicated to outfitting graffiti writers, artists and protesters with open source tools for urban communication. The goal of the G.R.L. is to technologically empower individuals to creatively alter and reclaim their surroundings from commercial and corporate culture. G.R.L. agents are currently working in the lab and in the field to develop and test a range of experimental technologies for the state-of-the-art graffiti writer."
Check out the ingenious design for carrying the equipment: