Take 3/4" copper tubing cut to about 6" long. Drill random holes all over it. I use 1/4" holes and it works well. Slide a piece of garden hose inside and throw it in the fire. You'll get cool blues and greens. When it's done, use a stick to pull out the pipe and stick another peice of hose in. You'll get about 10 uses before the pipe gets too soft and goes flat.
Duane
PS - don't cook over it. CAN'T BE GOOD FOR YOU!!