The Graffiti Research Lab is a group that promotes public art, in this case - graffiti. However, graffiti in the sense of art placed on public property, not necessarily criminally vandalizing a wall, their art is much more sophisticated than that. The Graffiti Research Lab utilizes technology to create less than commonplace art that can still be seen in public, except it actually can be regarded as art instead of a teenager spray painting their alias on private property.
One of their works came in the form of "LED Throwies." These are LED markers that can be self-made with 10mm LED's, button-size lithium battery, and a strong magnet all taped together. Then, these "throwies" can be thrown on any magnetic surface (preferably out of the reach of people who might want to spoil the fun) and stay lit for around two weeks. Also, if bought in bulk, each throwie can cost less than $1. The cool thing about these is that it doesn't deface property or cause any damage whatsoever. It is merely a light, or depending on the artist, be an actual design or picture if enough LED's are used. If I saw one of these in public, I think I would be more appreciate than apprehensive. I think the fact that it lights up would intrigue most viewers and since it's removable it really does no harm.

Similarly, the same group created a pixelated graffiti printer that allows you to tag an entire wall (or car) using a customized dot matrix message. This rig costs $280 and uses 7 cans of spray paint that's controlled by Arduino and solenoid valves to print a message when dragged across a surface. Using this device you can create large written messages in sort of a "propaganda" sense, very efficient and cleanly.
Not necessarily more artistic than normal graffiti; it provides a new medium and application of creating art, and shows how technology is used to simplify - and totally reinvent - the process of creating street art or graffiti. A video of the rig being demonstrated can be seen
here