For a split second there, it looked like graffiti's future was purely virtual. There was the Wiispray controller, which simulated tagging down to the paint drips; and before that there were a number of "light graffiti" projects. But the taggers? They flouted that, and the medium has evolved: Fire tagging, as its known, is the process of spraying your tag, then lighting it on fire before the paint dries.
As Nylon's blog notes, Ellis G, a well-known street artst formerly known for his drawings in chalk, is now "obsessed" by firetagging. The paint doesn't burn off completely, though some kids are doing it in lighter fluid. Once the fire has burned out, the tag that remains is a wreathed in tendrils of char and soot--like a street version of Cai Guo-Qiang, who makes drawings by lighting gunpowder atop paper. That's assuming everything goes right--and in this case, we're talking about fire+accelerants+drywall (on occassion). In fact students in L.A., a couple years back, burned down part of their school while fire tagging.
UPDATE: Ellis G, the graffiti artist whose work first brought fire-tagging to our attention, has sent some more pics and information in to Today and Tomorrow. You can actually view some of the work in a current art show up in L.A. at the Carmichael Gallery. And here's the man at work: