John Nack just posted a link to an interesting website called the Graffiti Research Lab and their new large-scale, laser-based graffiti. It looks like the graffiti artist uses a laser pointer as though he/she is drawing on the distant building while a projector receives the signal and projects the image onto the side of said building. The software they use also adds an effect to the writing so it looks like the "spray paint" is running down the wall. It's really cool! Watch the video.