Just wasted about 30 mins playing with an Airzooka and a smoke machine. :D
Fill it full of dense smoke, fire it and you get the most amazing smoke rings. :D Just fire a small one and it's amazing to watch. Even better, I caught it all on vid. If I get chance later I'll convert it to computer. :)
Oh, and by the way I can't see a thing now, the whole departments full of bloody smoke. Won't be long before the fire engines are here at this rate. :o