http://www.unitednuclear.com/smoke.htm

By far, the most common smoke formula is the Potassium Nitrate/Sugar formula.It produces a white-gray smoke and is both easy, inexpensive & fun to make.The percentage of Potassium Nitrate and Sugar in this composition vary somewhat dependingon who you ask, but the 60/40 mix listed below is pretty common...

This stuff sounds perfect for plugging up the back of my guitar with. i'd just need to remove the tremolo springs and associated metalwork, stick the smoke gum in, seal the back up, create a path for it to travle out of the guitar then just figure out a way to light the bloody thing without breaking the seal


http://www.unitednuclear.com/supplies.htm