Boy howdy, you asked the million-dollar question... Smoke is a bear... Cotton is about the only thing that will work and even then, if you don't do it right, it looks like cotton instead of smoke... Frankly, it's help if told us what exactly you're looking to have smoking... I've had sucesses with spun glass "Angel hair" and fibeglass insulation as well as cotton, but the glass was used for muzzle-flashes and had grain-of-wheat light bulbs installed...